But such services won't work as consent can be revoked anytime. It doesn't matter if you signed a contract, you can at any point say "No" and the consent is gone.
I have the very unique life style that makes half of my friends also hard core geeks, d&d players, hairy sysadmin, or able to tell which multiverse this particular batman costume is. They are also doubting every of their moves : is it allowed, it it disrespectful, will the other one be offended or hurt ? They really don't have much sexual success.
I love both of my groups, and none in them exhibit any signs they are better or worse persons. But i didn't experience that explicitly asking for consent made things better.
Not being an asshole does, and is pretty much unrelated to sex.
See, we've almost got this built!
Not that I think this tech should exist or be necessary in the first place.
Something we as a society, especially when it comes to tech, need to strive for much more.
A website/app where you can quickly declare consent for a specific activity, and share that declaration privately with a specific other user of the app. Each entry is secure/private to only you and the person you share it with. The entries are timestamped, you cannot delete them.
Then before the act, you quickly do a consent exchange and each person has the proof that the other consented.
You could make the entries visible only for a period of time to their own users, after which they are only accessible if there is a legal process, to avoid them being used as trophies/outing.
Obligatory Dave Chapelle Love contracts: http://www.cc.com/video-clips/jwmvxd/chappelle-s-show-love-c...