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title: Pebble SDK 2.5 - Changelog
date: 2014-09-18
---

>If you are upgrading from a previous version of the SDK, you will need to run the `pebble clean` command before using the SDK 2.5 with your project.

##Major Changes
* FW 2.5 includes an optimized version of ``snprintf`` (and related functions like ``APP_LOG``, etc) that does not support some length format specifiers previously supported (%hh, %ll, %j, %z, %t). The list of supported specifiers has been updated in the ``snprintf`` documentation. For those of you that use these previously-supported specifiers, please do not hesitate to [contact us](/contact) and we'd be happy to assist you with updating your code.
* Added [compass](/guides/events-and-services/compass) support.
* Enforced versionLabel formatting in appinfo.json in preparation for app auto updates.
* Added support for Pebble app relaunch on iOS when a Pebble watch is in proximity.
* Added notification dismissal support on iOS8.
* Added emoji support to Pebble notifications and system fonts.


## Detailed List of Changes:
### Changes for Firmware:
* Added functions ``heap_bytes_free`` and ``heap_bytes_used`` to view current heap memory usage.
* Added support for ``uuid_equal`` and ``uuid_to_string``.
* Added function ``accel_raw_data_service_subscribe`` to get accelerometer data with a single timestamp for all samples (significantly reduces memory usage for apps that do not depend on timestamps).
* Added [compass](/guides/events-and-services/compass) support.
* Added emoji support to Pebble notifications and system fonts `GOTHIC_24_BOLD`, `GOTHIC_18` and `GOTHIC_18_BOLD`.
* Fixed a bug that would cause a crash if a screen shot was taken while one was already in progress.
* Fixed an issue where Pebble APIs would use non-reentrant versions of standard C functions causing unexpected changes to return values.
* Fixed a bug with accel_service that could result in memory being freed twice.
* Fixed a bug where Golf API would show stale information on disconnect.
* Fixed a bug that prevented calling ``menu_layer_set_selected_index`` before ``menu_layer_set_callbacks``.
* Fixed a bug which would sometimes cause the command line logging tool to crash when a watchapp crashed.
* Fixed a bug that would cause the sample rate of the accelerometer to be reset when subscribing.
* Added support for Pebble app relaunch on iOS when a Pebble watch is in proximity.
* Added support for notification dismissal on iOS8.
* Fixed numerous bluetooth reliability & connection issues.
* Fixed a reset and other various bugs related to Data Logging.
* Fixed a bug that allowed backing out of FW update screen.
* Fixed a bug that would cause animations between windows to be slow.
* Fixed a bug where the Date UI would allow selection of invalid dates.
* Fixed a bug which would prevent the down button from scrolling through notification history.
* Fixed a bug with AVRCP that could lead to a crash.
* Set backlight to stay on during alarm ringing.
* Changed the default backlight setting to AUTO.
* Fixed a bug which would allow developers to ask for more than 25 accel samples per update.
* Added check for NULL parameter in ``gpath_draw_filled``.

### Changes for PebbleKit iOS:

PebbleKit iOS has been removed from the SDK download. Please find the latest PebbleKit iOS on [GitHub](https://github.com/pebble/pebble-ios-sdk) or on [CocoaPods](http://cocoapods.org/) under 'PebbleKit'.

### Changes for PebbleKit Android:

PebbleKit Android has been removed from the SDK download. Please find the latest PebbleKit Android on [GitHub](https://github.com/pebble/pebble-android-sdk).

### Changes for SDK Tools:

* Enforced versionLabel formatting in appinfo.json in preparation for app auto updates.

### Changes for Examples:

* Added [compass example]({{site.links.examples_org}}/feature-compass) application.

### Changes for Documentation:
* Added ``CompassService`` API document.
* Added missing ``calloc`` and ``realloc`` documentation.
* Improved ``tick_timer_service_subscribe`` documentation.
* Added missing ``RotBitmapLayer`` documentation.
* Corrected ``window_single_click_subscribe``	API entry.
* Corrected time_t time() function to specify that epoch adjusts for timezone and DST.
* Fixed typo in the ``AppMessage`` documentation.
* Improved ``gbitmap_create_with_data`` documentation.
* Fixed typo in documentation for ``resource_get_handle``.