My MOTA backup battery for my iPhone 4 (which I bought thru Groupon) failed after 11 months. Per instructions in the manual. which stated "1 year limited warrenty", sent the requested information to MOTA & and to it's main company, UNorth. I received an email from Dustin that a replacement would be sent. After three weeks, email inquiries as to when I could get a replacement went unanswered. Nothing! I sent all the emails to Groupon for their input and they replied that the unit was sold "without warranty." Nowhere in the ad, acknowledgement, or shipping receipt was this stated, nor in MOTA's instruction booklet. Groupon say "Tuff S***"!!! BEWARE if you buy electronics thru Groupon, it may not include the warranty protection you expect, or it it that the discount is based on warranty avoidance.?