Are there any apps built with Backendless that have a discovery section and/or suggestions, like social networks and marketplaces tend to have? And how seamless is it to integrate such a feature?
Our SDK have samples for simple actions, which you may use for implementation similar logic in your app.
E.g. fro Android they are here: https://github.com/Backendless/Android-SDK/tree/master/samples
Also with our new functionality UI-Builder you may use so called blueprints (will see them during app creation). For now there are two blueprints, but new ones are in process to be released.
Do not miss our Blog.
There are plenty of examples.