On some phones (e.g. Samsung phones), “deep sleeping apps” are applications that the system prevents from running in the background to save battery and improve performance. Apps can be put into deep sleep automatically by the phone when they haven’t been used for a long time. This can happen to any app. When an app is placed in the deep sleep list, it cannot send notifications.
Apps in deep sleep cannot receive notifications anymore
When applying a burst or longitidunal design, where you plan to halt sending questionnaires to a participant for a certain amount of time (e.g. a month or more), it is important to take this into account. For example, if there is a long gap between questionnaires, the participant will also not open the app for a long time. This may cause the app to be placed in deep sleep mode, preventing m-path from receiving notifications.
To make sure studies can run smoothly, we propose the following:
- Regularly send a questionnaire to m-Path app users (e.g. weekly). This can be a very short questionnaire and doesnt even need to contain actual questions. The goal is simply that the participant sometimes opens m-Path to prevent the app going into deep sleep mode.
- If this is not possible, take into account that some apps may be in deep sleep mode when a new burst starts. At that point some participants will not receive notifications anymore. These participants will need to remove the app from deep sleep mode:
- Sometimes simply opening the app is enough for activating them again.
- Its best to manually remove the app from sleep mode and then open the app to be sure.
- If participants still don’t receive notifications, participants should uninstall the app and install the app again. If they use their recovery code the study will simply continue and the participant will have the same participant ID.