Mobile IDs became available in Illinois on Wednesday, but due to the high demand, some residents are finding themselves waiting a little bit longer. 

A number of residents trying to download the digital ID to their Apple wallet received the following message: "Due to the high volume, your state's service is currently busy." 

Users can then answer the question, "Do you want to be notified when it becomes available?" 

In a statement, the Secretary of State's office confirmed the mobile IDs will roll out to Illinoisans in "phases throughout the day" and users should check back throughout the day. 

How to download your Illinois mobile ID 

Residents can go into their Apple Wallets, tap the "plus" button in the top right corner, select "driver's license and ID cards," and then follow the prompts to pull up their license or state ID.

Residents will need to use their iPhones to scan their physical driver's license or state ID card, and take a selfie that will be securely provided to the issuing state for verification. For one more security step, residents will also need to complete a series of facial and head movements.

Once approved, residents can then present their ID using their iPhone or Apple Watch. It will be accepted in person, online, and in apps at select businesses and organizations — including Transportation Security Administration checkpoints at more than 250 U.S. airports. Chicago's O'Hare and Midway international airports are among them.

ID security concerns addressed 

Secretary of State Alexi Giannoulias said digital IDs will be protected by the same privacy and encryption technology used for tap-to-pay and digital airline boarding passes.

"This is government innovation at its best — modern, secure, and designed for you," said Giannoulias.

Giannoulias said the hope is to better protect people's privacy.

If a bar or venue needs to confirm someone is over 21, they will only see that information. Residents can choose to hide information like their address and even their birthdate.

The Illinois Mobile ID program will also soon expand to Google and Samsung wallets.

The digital IDs are not a replacement for physical IDs, which still must be carried.