I know this might sound dumb, but are those devices paired to another device?
If you’re just now trying to use the Nexus 7 tablet for TR, it’s possible that your NEO, HR strap, and cadence sensor are still paired to a phone you’ve been using to train?
We have users and employees training with the Nexus 7 and I haven’t heard of problems with BT connectivity on these devices. What I’d recommend is unpairing your trainer and accessories from the TR app on whatever device you had been using, then try again on the tablet. Bluetooth devices can only pair to one receiver at a time so if they’re already paired somewhere else, they’ll be invisible to TrainerRoad.