BLE is an app that allows you to timeline any kind of data that is of importance to you. You can create different timelines for different kind of data. You can have a timeline for your pets health, another one for your vehicle service history and maybe a third one for a long lasting paperwork related case that has been dragging on for ages.
You can also share those timelines to other users. When you do that, a shared user can view, update existing or create new entries to your shared timeline. If we consider the examples mentioned above, shared users could be your pets vet, your cars vehicle mechanic and finally your legal advisor.