Chalk up another interesting development in the story of Google’s upcoming Project Ara modular smartphone: it’ll allow you to remove and replace modules while it’s still switched on.

According to Google’s Paul Eremenko, you’ll be able to hot swap every component in a Project Ara phone except the display and the CPU. And you’ll even be able to do it while processes are running, thanks to Ara’s OS – a modified version of the upcoming Android L.

Eremenko delivered a keynote presentation at the LCU14 conference in which he spoke at length about Project Ara’s development and its goals (you can see the entire 30-minute speech in the video embedded below, the presentation starts at the 44:12 mark), and touched on the hot swappable nature of the upcoming Ara modules. The modules, according to PhoneBloks, will be available to buy through a new, Google Play-style online store.