Screenshot by Steven Musil/CNET

Customers who switched away from the iPhones have always had one nagging problem: iMessage. Now, Apple has an app for that.

Apple quietly introduced a new tool in the last couple of days that solves one of the biggest headaches former iPhone owners have: lost messages.

The problem begins when iPhone users sign up for iMessage in the first place. The service, which Apple introduced in 2011, helps iPhone users communicate with one another over data networks and Wi-Fi, instead of using text messages on cellular networks. To do this, Apple keeps track of a user's phone number so that when another iPhone user tries to send a message, it can shift to iMessage instead.

What happens if users no longer own an iPhone? Until now, they had to turn off iMessage on their old phone before turning on a shiny new Android or Windows Phone device (or BlackBerry, if that's your thing). Some users, however, have said turning off iMessage doesn't always solve the problem.

Unhappy users former iPhone owners have sued the tech titan over the issue, complaining they fell into a void where iMessage texts do not travel. Worse, the sender usually thinks the message was delivered even though it never was.

Apple's new tool includes step-by-step instructions for de-registering iPhones still in the possession of their former users. And for those who longer have their iPhone, the page includes an option for typing in their phone number and receiving a confirmation code that can be entered to confirm their choice.

Apple did not immediately respond to a request for comment on the new tool.

CNET's Nick Statt contributed to this report.