The Strava Android app depends on location services, which require extra battery power beyond what would be used when the phone is in standby mode.
There are some things to keep in mind that can reduce the battery's discharge rate while running Strava. As a general guideline, we have observed modern phones successfully recording more than 5 hours of activity.
Old devices have old batteries
Older phones have two factors that contribute to poor battery performance. First, as batteries get repeatedly charged and discharged, their capacity slowly decreases. So a phone that has been recharged a few hundred times will perform worse than when it was new. Second, battery density continues to improve with technology advancement so a modern phone will have better performance potential than an older model.
In general, the idea is to turn off parts of the phone that are not necessary during your ride. By adjusting settings, you can turn off applications and functions so the phone will have more battery power to run Strava for a longer period of time. Don't forget to reset the changes you make to your phone's settings.
Mobile devices use backlights or LEDs to create the light shown by their displays. These lights use a large amount of energy, so you should minimize or avoid the use of the screen while recording a very long activity.
Airplane mode is a convenient setting that disables all voice and data radio communication on the phone. In most cases, the GPS capability is still enabled, but there are some considerations to keep in mind. For instance, some Motorola devices disable the GPS in airplane mode so be sure and test this out beforehand. An obvious side effect of this is that the phone will not be able to make or receive calls, texts, tweets, notifications, etc. as long as airplane mode is enabled.
If you want to be able to receive voice calls, you can turn off data communication and save battery. SMS messages should still work, both sending and receiving. You can disable data communication by following the path below:
Settings > Wireless & Networks > Mobile Networks > Data Enabled
If you are in airplane mode, the rest of the suggestions involving communication settings will not provide further help. However, if you don't want to use airplane mode, some of the suggestions below can help.
While it won't make a significant difference, you can also turn off Data Sync, Bluetooth, Wifi & NFC if you're not using them.
Strava Beacon, Strava Live Segments and Audio Announcements require cellular data so these features will not work in airplane mode and could contribute to battery drain. Consider disabling these features if you're hoping to conserve battery.
Android is able to report on what is using the most energy. Check the information in the "Battery use" setting to figure out what is draining your battery and address it by shutting down, adjusting, avoiding, or removing major energy drains. Keep an eye out for applications that run in the background and periodically request network communication.