The popular Bitstrips comic app has been taking over Facebook, but now the Bitstrips mobile and Facebook apps are down, due to servers being overloaded.

The Bitstrips Facebook and mobile apps are down as of Friday morning, due to a surge in popularity resulting in server errors, IB Times reports.

On Friday morning, the Bitstrips app on Facebook was down with an error message reading: "We are currently performing some routine maintenance. We should be back in about an hour."

Bitstrips' Twitter has been responding to questions from fans upset that the comics-making app is down.

"The update is just to perform server maintenance. Apologies for the inconvenience," it wrote.

Another tweet from Bitstrips Twitter account said: "Servers are overloaded and FB & Mobile apps down. Working hard on getting them back up and running ASAP. Thank you for your patience."

So what exactly is the Bitstrips app? Read on to find out everything you need to know about the comic app taking over Facebook.

The Bitstrips app was launched on Facebook in December 2012, but the company just released its iPhone app at the end of September and updated it earlier this week, along with its Android app, ABC News reports.

If you're on your phone, you can sign in using your Facebook account and start designing the cartoon version of yourself, such as your hairstyle, makeup, the size of your face, and your outfit.

Then you can choose from a number of different comic scenes; there are more than 1,000 comic templates, and the company adds new ones every day, ABC News reports.

You can adjust the text below and even invite a Facebook friend to co-star in your comic strip. Once you've finished your comic, you can post it on Facebook, or if you're on your phone you can save or share the image on another service.