I agree with all sandi said. You are in my shoes 4 months or so ago trying to bring this all back together. July-September '15 were filled with anxiety about all aspects of a recovering WAW and MR. Every time she picked up her phone...
What I did for transparency was I made it completely clear to my wife through boundaries what I expected from her. In my sitch, the worst offender was the &$*%ing phone and #*&*ing social media. She knew that I would not let her back into the home or my life, beyond being co-parents to S6, if she did not respect that part of transparency. The first weekend she moved back, which I so slickly made the Retrouvaille weekend, I had access to phone and social media any time I chose. I've only checked a couple times. You may need more. The important thing is that you make them non-negotiable.
That being said, what is it that you absolutely, at a minimum, and reasonably require for transparency? I say minimum, because if you set the bar too high, it will be impossible for her to meet, and this is about the two of you coming back to the marriage. If a photo with grandpa is good enough, so be it. If you need the GPS, then request it. You decide what will help you trust.
M: 8.5 T:10 Me:37 W:34 S:6
Retrouvaille and W moves back- 7/31/15 Piecing - 7/4/15 to present