The semantic web and social linked data. We could have applications share data without depending on big tech, but rather based on application standards.
It can be used today and gains traction but I wouldn't mind it going faster. Especially the interoperable personal app space could use some love and attention.
Exactly. The Semantic Web is broader than Solid but Solid is great for personal apps.
Say you buy a smartphone. The specifications of the smartphone likely belong elsewhere than in a Solid Personal Online Datastore, but they can be pulled in from semantic data on the product website. Your own proof of purchase is a great candidate for a Solid POD, as is the trace of any repairs made to it.
These technologies are great to cross the barriers between applications. If we'd embrace this, it would be trivial to find the screen protector matching your exact smartphone because we'd have an identifier to discover its type and specifications. Heck, any product search would be easier if you could combine sources and compare with what you already have.
The sharing tech exists. Building apps works also. Interpreting the information without building a dedicated interface seems lacking for laymen.