Boundanna was one of the first sites I discovered on my journey. It has a good old-fashioned forum as well as tutorials on tying, as well as advice on safe self-bondage.
Chastify is now my favourite site, it has a downloadable app. It can directly control a variety of bluetooth devices. It can also be set up so that a keyholder can lock down a phone and even take screenshot if you’re brave enough! It has a variety of bots and you can even have an AI keyholder!
This is my second favourite chastity site. Its similar to chastify but it doesn’t have the advanced features. It is still well-laid out functional and seems to have a larger community. Subs have experienced issues with moderation, but all in all it is a good app.
This place has some really insane devices especially the 2B. It can be quite pricey but is honestly worth the investment. The 2B box can be controlled over the internet and the sensations are completely out of this world