I have been using OneDrop since February 28, 2017. I hadn't had any error strips until this week. I have had 10 error strips in the past three days and have reported it to OneDrop. They are sending me Control Solution and will be talking to me after I receive it.
I just got my A1C result and have gone down from a terrible 9.3 (had trouble getting insulin prescriptions so I "let things slide" and wasn't testing because I knew it would be high since I reduced insulin to make what I had last.) My A1C is now 7.2. I am trying to get it down to 6.0.
I like being able to test as often as I want, and having adequate insulin has further enabled me to give the right dose of basal and bolus. I've managed to stockpile some insulin too.
Being perfectly honest about it, I didn't start doing the "right" things until I started OneDrop. I didn't get my insulin prescription refills until the end of January, but I was still in a bad frame of mind for another month.
I am a data/numbers driven person, and seeing the BG's, Carbs, Insulin units and Exercise on my phone has motivated me more than anything else has.