It will drain your phone's battery regardless of how old it is. I read the battery tips article. When I turn off sync, app says that option must be on for it to work. I keep the phone in my pocket, using it only to log bicycle rides, not even for music. The only thing I could still do is to turn off WiFi, but instead I've decided to log the ride with Specialized Mission Control free app b/c even if the map sucks, it won't drain the battery. Unfortunately, Komoot app is mostly useless.