You should find a way to waterproof it, use ployurethane tape or cellophane, get two bottles of the gel (dark color or even a solid black bottle that can have a pinhole put in it through the label...which should then be scuffed up to not be obvious. Use some sugru or something to keep it in place, then just pour gel in around it. That way if someone picks it up it'll still work.
Cool points if you make a plug out of sugru to cover the usb connector so you can just extract data with a cable and leave your contraption put together.
Waterproof that bitch and make sure you don't fucking record yourself setting it up like a fucking dumbass, maintain some deniability.
You do NOT want someone to pick that shit up and figure it out...when the push button cap doesn't work..what now? They will unscrew the cap or start fucking with the bottle. Don't be stupid, think of what happens if you get caught. You are royally fucked, so don't let it happen.
