One glaring thing I would mention is that your testing budget is way too small for this offer. $100 budget is more for payouts in the $0.50-$2.00 range. As you can see in Ryan's latest video, he spent something like $12,000 to test a high payout campaign, and that was before he did any serious optimizing. I'd say you'd need at least $500, if not $1,000 to test this offer. Minimum.
Also, just because you can target Android and iOS doesn't mean you should, especially with a small budget. By spending the entire thing on one OS, you will be able to get better data than spreading it out to multiple OS's. I would start with Android just like you did if you are only going to spend $100, and if you get it profitable at a later date, then use the profits to test iOS.
By the way, I think all of us make the mistake you made at least once, so just be glad you did this when you were spending $50 instead of $5,000