SideloadBox is the iPA Library you deserve. A place to get all of the latest tweaked apps and emulators.
SideloadBox requires Cydia Impactor in order to install applications. Check out the link in the toolbar on the right on how to install apps with Cydia Impactor.
There are other ways of installing these iPAs. If you have a jailbroken device, get Appsync from Angelxwind's Repo here. For clarity on how to do this, watch iDeviceHelp's video.
Then... stick to the regular TweakBox. This site was made as an alternate service to TweakBox. Occasionally we would have signed apps appear on here, and will notify you via application descriptions.