Tap the "No cloud mode" button. The app will only store dive log information locally on your device. Following installation an empty dive log is created.

The Subsurface maintainer provides a dedicated and free Internet cloud storage account for users of Subsurface and Subsurface-mobile. You can use this to store your dive log and to share your data between several computers and devices. The Subsurface team never accesses your dive data without explicit permission to do so, the data are not used for any other purpose than providing them to the user who created them. There are no ads and no harvesting / analysis of the data / monetization of data on the Subsurface Cloud storage.

Subsurface-mobile is sufficient to fully maintain a dive log. In addition you can use the more advanced features in Subsurface when you have access to a computer while still being able to work with your dive data when only a mobile device is available.

The dive data in the cloud are cached locally on any device or computer that is connected to the Subsurface Cloud account. It is easy to create backups of the data (for example in XML format) on the desktop: both the mobile device and the desktop keep a local copy of the data so that the dive log is always accessible, even without an Internet connection.

To create a Subsurface Cloud account follow these steps:

1) Enter an e-mail address and a password in the fields indicated on the screen (see image above). The e-mail address should be in lower case and the password should contain a combination of upper and lower case letters and/or numbers.

2) Tap the "Sign-in or Register" button.

If you have already set up an account on a different computer or device, simply enter the same credentials here. Subsurface-mobile will now download your existing dive log data. Once the dive list has been downloaded from the cloud, Subsurface-mobile usually works only with the the local copy on the mobile device. This avoids long delays or even failure of operations if there is poor internet connectivity. Remember to manually sync with the server after making local changes (either by pulling down on the dive list, or by using the manual sync entry in the Dive management menu entry).

3) If this is a new cloud account, a PIN screen will open (see right image above). A PIN is e-mailed to the email address entered in the previous step. Enter this PIN into the field indicated and tap the Register button. After the PIN has been entered it is no longer needed - it just proves that this is indeed your email account.

A video-tutorial is available that demonstrates how to connect to the cloud.

At this point a new account has been created for you on the cloud server and access to the cloud is enabled. In this case the dive list is initially empty. Start entering dives in the dive log or download dive information from a supported dive computer.

Once registered, Subsurface-mobile remembers the cloud credentials and it is not necessary to provide these again when launching the program.

The dive log can be updated automatically. If there is Internet connectivity, Subsurface-mobile accesses the cloud-based dive log to verify that the local copy of the dive log is still the same as the log in the cloud server. If not, the local copy and the copy on the server are synchronized.

When you tap on a dive in the Dive List, a Dive Details page with the dive profile and many important details about the dive is opened (image on right above). You can use a pinch gesture to zoom into the profile. Tapping and holding with one finger (until the profile becomes translucent) allows you to pan the profile and see more details in specific parts of the profile.

You can view other dives by swiping the Details view to the right (for the previous dive) or to the left (next dive). Using the Action Bar, it is also possible to delete the dive (tap the Trash Icon on the Action Bar) or to view the dive location on an integrated map viewer.

The context menu (accessible by tapping on the vertical three dots in the lower right corner of the screen) offers additional options to move dives between trips, the same delete and map options already mentioned, and access to the undo and redo facility that allows you to step backwards and forwards through recent changes.

In the Details View, you can either tap the name of a dive site or the GPS pin on the left hand side of the Action Button at the bottom of the screen in order to open a map with the dive site in an integrated map viewer. This of course is only possible if the dive site is associated with GPS information.

By default, all the dives in the dive log are shown in the dive list. After several years your dive log can become quite long and, sometimes, you might like to list only the dives of a particular type, e.g. those at a particular dive site or those with a specific buddy or dive master. Use the Filter to achieve this. The filter mechanism searches through all the information for each dive, looking for one or more key words. Only the dives containing these key words are listed in the dive list. To Filter the dive list, tap the Filter action button:

at the bottom of the dive list. A text box appears at the top of the screen (image below). Type the word(s) that you would like to use as a filter.

Three filter modes exist. "Fulltext" searches all text strings. Selecting "People" lists buddies and dive masters, while "Tags" only filters for tags containing the given text. Filters are not case-sensitive. To clear the filter, remove the key words from the text box and select the Filter action button to switch off filtering. The image above represents a full-text search for dives with the word "nitrox".

This video-tutorial explains how to add information to a manually-entered dive.

You can manually add a dive to the existing dive list. On the dive list tap the "plus" sign in the action bar, or use the main menu and tap Dive management → Add dive manually. This opens a screen that is identical to the editing screen discussed above. When a dive is added manually, you cannot directly add a dive profile from a dive computer. However, if you do not use a dive computer, the duration, depth and several other bits of information about the new dive can be entered. The Action button at the bottom of the screen contains a disk symbol. Tap this to save the new dive. To cancel any edits, tap the Back button. The left-hand image below shows a screenshot of a dive being created and the right-hand image shows the same dive in Details View. After editing the dive information, the dive trip information needs to be edited as described in the section above on Dive trip editing.

There are several ways to get to the Download Page. You can either tap on the main Action Button on the bottom of the Dive List, or you can select Dive management → Download from DC in the main menu. On Android devices, when you plug in a USB serial cable for a dive computer, the Download Page will be opened automatically. A screen is shown requiring that the user specify the names of the vendor and model of the dive computer. For instance, when using a Shearwater Petrel dive computer, the vendor is Shearwater and the Dive computer name is Petrel (see image on the left, below). Caveats: The download feature in smartphones supports only a limited number of dive computers. On Android devices these are typically dive computers using a serial USB interface using a USB OTG cable or a simple USB C-A adapter on newer devices. Android devices also support Bluetooth dive computers that are supported in Subsurface on the desktop. Both Android and iOS devices allow direct download of dive data from a handful of Bluetooth LE enabled dive computers. Use the Vendor name and Dive Computer drop-downs to pick the correct dive computer. When downloading from multiple different dive computers, shortcut buttons appear below the drop-downs to easily switch between them. In the Settings menu you can remove these buttons, a useful feature for removing buttons of dive computers that are not used any more. Achieve this by selecting the option Forget remembered dive computers in the Settings menu. After all these caveats, let us proceed with download.

TODO: image of DL missing - or link to the 7.2.3 Start the download

When downloading from multiple different dive computers, shortcut buttons appear below the drop-downs to easily switch between them. In the Settings menu you can remove these buttons, a useful feature for removing buttons of dive computers that you do not use any more. Achieve this by selecting the option Forget remembered dive computers in the Settings menu.

This video-tutorial explains how to add information about a dive.

At the bottom of the Dive Details screen the action button is a pencil. Tapping the pencil button changes the page and enables edit boxes that allow modifying the existing dive information, e.g. adding text to the dive notes or changing the names or values of some of the information (see image above). It may be necessary to scroll the window to access all the information. At the bottom of the edit screen is a Save action button. Tap this to save the new information, after which the dive list screen is updated and shown. To cancel any edits, tap the Android Back Button or the application back button at the top left of the screen on iOS.

Delete a dive from the dive list by long-pressing a dive and selecting delete in the context menu. If the wrong dive was deleted by mistake you can easily undo the operation by using the context menu.

As the name indicates, this ensures that the local changes on the mobile device and changes made by other devices and computers to the data stored in the Subsurface Cloud are synchronized. It is highly recommended to sync with cloud storage after downloading new dives from a dive computer or after manually adding or editing dive information on the mobile device. This can also be triggered by pulling down (and briefly holding) the topmost entry of the Dive List.

By default Subsurface-mobile runs offline and only syncs the dive list with cloud storage when explicitly told to do so (see the previous entry above). You can choose to always sync with the cloud server. This is not recommended unless you are in an area with a fast and reliable Internet connection, as otherwise Subsurface-mobile might appear to hang between operations as it tries to connect to the cloud server. Selecting Enable cloud auto sync causes the local dive log to be synchronized with the copy in the cloud after most changes as well as (on Android) every time that Subsurface-mobile is closed. iOS doesn’t support the concept of closing an app (you can just kill it, which doesn’t allow for a final sync with the cloud). In general it is safer to manually sync with the cloud once you are done making changes in Subsurface-mobile.

In many cases the values of the Base Variable along the horizontal axis are shown by dots, not numbers or names (Image B above). This is because the screen of a mobile device often is not wide enough to show all the values, especially prevalent in bar charts where the labels along the bottom axis are long. There are two ways of addressing this problem:

By default, when the Statistics panel is opened, a histogram is shown of the number of dives performed each year. This is an example of counts data. To request a graph representing counts, three comboboxes need to be set:

a) The top left combobox of the Base variable needs to be specified. Which variable should be along the horizontal axis? Examples are Year, Buddy, Rating, Max. depth.

b) The binning combobox (top right) for the Base variable needs to be specified. This represents the increment for each bar along the horizontal axis. For instance, when counts of number of dives are extracted for years, this could be in increments of a year, a quarter (3 month period) or a month. For some variables, e.g. Buddy or Rating, a binning value is not relevant and cannot be selected. However, for others, e.g. Year or Max. depth, selecting the appropriate binning is important.

c) For simple counts data, the left combobox of the Data variable needs to be set to "none". This is because a data variable is not involved in this type of graph. Divers used to spreadsheets may prefer a pie chart for these data, achieved by selecting "piechart" from the Chart type combobox. It is possible to simultaneously provide counts for two variables. In this case one could specify a Data variable which results in the counts being subdivided according to the data variable. This option does not have a piechart equivalent.

For simple histograms, the default height of each bar is determined by the mean value for the observations included in each bar. However, this can be manipulated using the Operation combobox to show the mean, maximum, minimum, median and sum applicable to each bar. Image A below shows quarterly count data of dives while image B shows quarterly count data, subdivided by dive mode (some dives open circuit, other dives rebreather). The legend can be dragged around so that it does not obscure part of the graph.

As mentioned in the section above, bar-charts showing a breakdown of each category for a number of subcategories are easily created.

a) Select a variable with categories (along the horizontal axis) as a Base variable (e.g. dive mode or suite type).

b) Select another category of data as a Data variable (e.g. gas type or cylinder type).

The images below show two alternative bar-chart representations. If, in the Chart type combobox, one selects "Barchart/stacked vertical", a graph similar to image A below is generated, summarizing a log of technical dives where, for each cylinder gas type, the bar is subdivided into a count for open-circuit dives and for rebreather dives. On the other hand, if "Barchart/grouped horizontal" is selected in the Chart type combobox, a graph similar to image B, below, is produced. Here the subdivision within each gas type is shown as adjacent bars.

For the dataset in the image above the SAC rate appears to have decreased over time. If the relationship between the two variables is statistically significant, a red line is shown that summarizes the best estimate of the relationship between SAC rate and year. In this graph it appears that SAC rate has decreased from around 21 l/min to around 14 l/min between 2013 and 2021. The pink area around the red line indicates the uncertainty of the precise orientation of the line. The line is expected to lie somewhere within the pink area with a certainty of 95%. The intensity of the pink color also indicates the relative reliability of these estimates. The procedure for obtaining a scattergrapth is:

a) Specify the Base variable: Which variable should be along the horizontal axis? Examples are Date, Temperature, Max. depth, SAC rate.

b) Set the binning value for the Base variable (top right) to "none".

c) Specify the Data variable: Which variable should be along the vertical axis?

You might wish to compare different categories of dives. Is the (5-star) Rating of a dive related to water temperature? Is my SAC rate related to diving with different dive suits? Since dive suit and Rating are categories, a scattergraph is not appropriate. The default is a categorical dot graph, which, in the case of image A below, shows the precise water temperatures for each Rating. The red lines indicate the top quartile, the mean and the lower quartile of temperature for each rating. The column with no star indicates dives for which a Rating has not been selected. It appears that dives with a 5-star rating have higher temperatures than the other ratings. To obtain a categorical graph:

a) Select a variable with categories (along the horizontal axis) as a Base variable (Top left).

b) Select the data variable and set binning to "none" (middle right combobox).

c) By default the Chart type combobox shows "Categorical/data points". If this is not the case, select this value.

Alternatively you could create a Box-whisker graph for the same data. In the Chart type combobox, select Categorical/"box-whisker". This creates a graph indicating the maximum, top quartile (Q3), median, bottom quartile (Q1) and minimum for each category or class. Image B above shows a box-whisker graph for the same data as image A above. You can see that the values for a Rating of 5 stars tend to be higher than for other ratings.

For most users, the defaults for tracking GPS locations are appropriate. If you would like to change them, go to the Main Menu, select the Settings screen, and open the Advanced area on that page where there is a section for configuring the GPS service (see image below). GPS location data are collected at regular intervals, e.g. every 5 minutes, or at regular distances, e.g. after the boat has moved more than 200m, or a combination of both of these approaches. Provide the appropriate information and tap the Back button. The program is now ready to collect GPS positions.

Collecting GPS fixes like this is relatively battery intensive and unfortunately both Android and especially iOS have become increasingly aggressive in killing applications that are running while the screen is turned off. It may make sense to check between dives that the location service is still running. On the other hand the battery consumption of a smartphone with GPS enabled is often significantly less than the battery consumption of a dedicated GPS that is logging a track.

From the Location submenu select Show GPS fixes. This brings up a list of GPS positions obtained by the location service (image below). Two actions are possible for each of the locations, enabled by dragging the right part of a location to the left. This exposes two options. Tapping the dustbin deletes this particular GPS location. Tapping the teardrop-shaped icon (actually a Google Maps pin) opens up Google Maps with a pin indicating the exact map position of the GPS record being viewed. The two above options can be hidden by drawing the GPS record to the right.

After running the location service during a dive trip, first either download the dives from your dive computer or manually enter the dives into the dive list. Now you can apply the GPS positions to these dives. From the Dive management menu, tap Apply GPS fixes. The dive list contains the start and end times of each dive. Now, Subsurface-mobile applies the first GPS position that falls within the dive period of each dive. This results in a GPS position for each dive that is saved as part of the dive log.

Here you can pick metric, imperial, or personalized units for the user interface. In most cases Subsurface-mobile should pick the regionally typical unit system for your location.

As the name indicates, most users do not need to make changes here.

This page shows you the exact version of Subsurface-mobile that you are running and provides a convenient way to copy the application logs to the clipboard.

This menu entry opens the online version of this user manual in the native browser of your device. Unfortunately this option is not available without Internet access.

This item opens your default email client with a pre-populated email to the Subsurface support alias and copies the app logs into that email. Simply add your question or the but that you are reporting and send us your message.

As mentioned earlier in this manual, this is a convenient link to a web page that allows you to reset the password for your Subsurface Cloud account.