A lot of these options are available on iOS only. The reason for this is that Apple provide direct access to their music system. Android's music system is more limited and more sophisicated music support is provided by 3rd parties (which this includes Google Music) which we do not have access to.
Audio can be assigned in both the timer editors and the interval editor.
When assigned in the timer editor the audio will play through the entire timer without any interruptions and any settings within the interval audio editors are ignored.
Tapping the No Audio Selected or the current audio selection will present the audio picker where you can choose which audio to assign.
When enabled the audio selection will be randomised if it contains more than one item.
Clears the music selection from this interval/timer.
Sync song changes with intervals
When enabled the audio selection will change song each time the interval changes.
The volume that the current music selection should play at.
The volume option only works when the internal audio player is used. However, we no longer recommended using the internal audio player as it will not play any music from an Apple Music subscription. The internal audio player and this option will both be removed in the future.
When enabled and the timer encounters an interval with the same music selection it will resume from where the previous interval stopped.
When enabled the music selection from this interval will continue playing until another interval with a music selection is reached.
How to play throughout a whole set
By only adding an audio selection to the first interval of a repeated list, and enabling the persist option the audio will play throughout the entire list, and then change when it reaches the first interval of the next set.
How to play audio per interval
The easy one. Just assign the audio to each interval. Optionally, if you wish the audio to resume where it left off you can enable the resume option.
Adding Music on Android
On Android you need to upload your music directly to the music directory of your device. Your music should not contain Digital Rights Management (DRM) or it will not play in Seconds.
Details of how to load music on to your device with a USB cable can be found here:
Spotify, and Other Streaming Services
Spotify is probably the most popular music platform available. However, we do not support it within the app as they have prohibitive terms & conditions, and a poor API that would actually require switching to and from the Spotify app each time you change an interval.
You can only play music from streaming music services such as Spotify, Google Music etc in the background while your timer is running but these services cannot be integrated into the timers.
iOS users should make sure the music is playing before they enter the timer screen to ensure the app is configured correctly for external music playback.