LG has revealed both a software development kit (SDK) and a hardware development kit (HDK) to developers, with the goal of encouraging an ecosystem of modules to clip into the LG G5‘s so-called Magic Slot. The kits will officially launch on Friday, April 15, at the fourth annual LG Developer Event in San Francisco.

The Korean consumer electronics manufacturer also announced a website, LGFriends.com, that will act as a marketplace for developers to offer their third-party modules. Currently the site only features first-party “Friends,” such as Cam Plus, 360 VR, and Rolling Bot.

The G5 is being heavily marketed as the company’s first “modular smartphone,” although that term is somewhat of a misnomer in this case. Whereas a true modular handset, like the Google’s Project Ara concept, allows nearly all of the components to be swapped out and/or upgraded, the G5 simply offers a removable battery cap that doubles as an accessory mounting point.

While past G-series phones have been widely praised for their design and functionality, reactions to the G5 have been decidedly mixed, with reviewers having been especially critical about some puzzling design choices; the rear, especially, feels like a hodgepodge of different, competing design philosophies. The one saving grace seems to be the ability to pop out and replace the battery, a feature rarely found on flagships anymore.