@habib, I think that’s the case for downloading the time lapse, but my understanding of the feature is that once you set it up the camera just records video to subdirectories within the time_lapse subdirectory off the root directory of the microSD card, so it essentially functions independent of the phone while it’s recording. When you want to retrieve the time lapse, your phone has to remain open to the screen where the compiled video file is downloading to your mobile device until that completes (there’s a Wishlist item asking for background downloading). I don’t know for certain if it’s necessary for the phone and camera to be on the same Wi-Fi network and haven’t tested this, but I wouldn’t be surprised if that’s the case.
I’d also note that if you set a time lapse to record and navigate back to the Timelapse screen for that camera, the app will tell you that it’s recording a time lapse and show you the expected end date. Then if you have a power outage during the time lapse and recording stops but doesn’t resume once power is restored, if you go back to the Timelapse screen the app will still tell you that the time lapse is recording and show an expected end time, but then there will be no recording to retrieve at the end; however, you know that some video was recorded, because you checked the microSD card later and found the record.h264 file and it played back in VLC up until the point power was lost. 
In my opinion…
- The camera should resume recording of the time lapse once power is restored. It has data files that tell it the parameters of the time lapse (start, end, interval), so it should check those and pick up where it left off.
- The app shouldn’t tell the user that a time lapse is ongoing if the camera isn’t actually recording.
- If a power outage happens and some video is recorded, the user should be able to retrieve this (see it in the Album) and delete it from the card without actually pulling the card from the camera.
This has been my very recent experience, anyway, but I haven’t yet gotten around to filing a bug report.
@LeDonMacaron, thanks for updating the tag! They can be tricky here in the Forum, and it’s easy to grab the wrong one.
I’m not sure why you’re looking to use a time lapse rather than regular microSD recording (either Continuous or Events Only) if you want something that’s closer to full-motion capture, but I s’pose you have your reasons. 
See this topic:
@ssummerlin posted with screenshots that describe what he mentioned above.