Craig Mod discusses single-purpose products in his product design essay There is much to learn from the paper towel:

All of these single-purpose tools or philosophies strive towards the same goal: whittle away the cruft around an idea to reveal its most base components, and in doing so, strengthen what is left.

The single-purpose lecture attendee is, in theory, a better student. The single-purpose-sized paper towel makes us happier, is gentler on the earth. Individual tools in unix are more efficient and easier to debug because of their specificity. Facebook Messenger on its own is easier to use to communicate without the deluge of Facebook notifications flying in our faces. And so on and so forth.

I’ve started using Craig’s solution for single-purpose Twitter notifications and single-purpose Facebook messages and it works really well.