I just recently bought a smart phone, and use it to play MP3’s that I download from Club Migros (Balades and L’avis de Marie podcasts), play music MP4’s of French artists, listen to French audiobooks in MP4 format on YouTube, and read my French language PDF’s.
Unfortunately, the Club Migros app is not available to me, since I live in the US. Others will find that application here.
Other smart phone apps that are available to me, are:
Learn 50 Languages
Learn 50 Languages – French