Currently the Android App forgets the last played song after several hours not using spotify.
Seems when it looses internet connection it forgets the song. ("Internet connection lost" message shown and the marking of the current song disappeared).
Spotify should save which song of which playlist has been played recently. So after startup of spotify the - one - last played song - should be marked. And a simple tap on "play" should resume the song.
On iPhone this feature already seems to be available.
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