The popSLATE is an iPhone 6 case that's designed with a 4-inch e-ink screen and a Bluetooth chip. It acts like a second display to the Apple device and is capable of showing images with low resolution of 240 by 400 in 16 shades of gray.

The popSLATE can display any images semi-permanently — including photos, artwork, grocery lists and even boarding passes. The idea behind it is being able to see the display anytime without having to unlock the device — which can drain the battery. Since popSLATE is made of an e-ink screen, there's also no need to use power in order to retain the images.

The popSLATE case can store up to eight images, which the user can swap around for the display. When a new image is entered, the oldest saved picture gets deleted automatically. Images can be gathered through the use of an app or they can come straight from the photo gallery.

While the process of displaying pictures should be fairly simple, managing them can be a little tricky. Moreover, there doesn't seem to be an easier option to delete a specific photo. In the future, popSLATE plans to add more functionality to the case. That will include the ability to manage stored images from the app and an image-uploading feature that will allow the user to make multiple image uploads at once.

"We recognized the existing mobile experience – constantly unlocking your phone to launch an app to access simple information, and burn up precious time and battery life – could be a lot more efficient," said Yashar Behzadi, founder and CEO of popSLATE. "We knew there had to be a better way to access data and images and have them accessible anytime — that your apps should work for you, rather than the other way around."  

Setting up the popSLATE prior to usage is very easy. After sliding the iPhone into the case, download the popSLATE app. Quick prompts will follow, saying whether the device is already paired to the case through Bluetooth.

The biggest draw for popSLATE is its independence from the iPhone's battery. The case is built with its own internal battery that can last up to a whole week on a single charge. It uses power only when an image is refreshed.

Priced at $130, many would-be users think the popSLATE should be able to deliver more than simply showing black and white images. But then, that feature may be more than enough for those who have always liked the idea of playing with photos and displaying them for everyone else to see.