When you put a case on your phone, you usually give up the ability to add on more accessories — be it a new camera lens, a card reader, or extra storage. So OtterBox is trying to change that. It's unveiling a new iPhone case today called the Universe, which protects a phone and allows its owner to clip on up to two accessories at the same time.

Square, Olloclip, and SanDisk are making compatible accessories

It's a pretty neat idea — and pretty simple, too. There are two slots on the back of the Universe case: one at the bottom, and another at the top. All you do is slide a compatible accessory in, and you're done. There are no electronics involved, so accessories have to plug into the iPhone's Lightning port or use Bluetooth if they need to connect.

Accessories will still need to be designed to fit into OtterBox's proprietary accessories slots. That's a pretty major downside to this system, but OtterBox is a big enough name that it may be able to get a lot of partners on board. Right out the gate, it's doing pretty well. It already has eight partners, including Square, Olloclip, and SanDisk. They'll all have compatible accessories available soon. Other add-ons include a battery pack, a Wi-Fi booster, and a tripod.

The case won't protect anything you attach to it, but OtterBox says Universe-compatible accessories are supposed to be able to withstand a fall. It's not clear if they'll be every bit as tough as the typical OtterBox case, but it would be pretty useful if they were. The Olloclip lens, for example, is something you definitely don't want to drop.

Modular phones are super trendy this year (even if none have actually taken off)

OtterBox is referring to "Universe" as a case system, meaning this accessory port will likely make its way to more OtterBox case models in the future. It's starting out on a fairly thin case, from OtterBox's "Symmetry" line. OtterBox says this is its faster growing market, though the huge "Defender" cases you probably know it for are still OtterBox's top seller. It's easy to imagine the accessory port coming to that line later on.

This first case will sell for $50. It goes on sale on OtterBox's site today, and will be in retail stores in about a week.

OtterBox seems to be on to something here. Being able to alter and expand a phone's hardware is quickly becoming the trend of 2016. This doesn't seem like the ideal way of expanding a phone's hardware, but it's easy to imagine people using it anyway if it's built right into their case.

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