Last week, Apple started rejecting apps from its mobile app store for using Unique Device Identifiers (UDIDs) that allow developers to distinguish between iPhones. That caused a major stir in the mobile app world, with developers scrambling to find an alternative. Developers have known for a few months that something like this was coming, which led to the creation of OpenUDID, a workaround global identifier.

But Crashlytics, the Boston-based mobile crash reporting company, today released an open source alternative called SecureUDID that the company believes addresses the balance between developer needs and user privacy.

It works by generating unique user IDs for each app, rather than a single global user identifier. So your iPhone would have an ID that differentiates it from other Pandora app users, say, and then a completely different ID to differentiates it from other Angry Birds users. That gives you some layer of privacy, while also letting developers differentiate between devices.

Though Crashlytics was involved in the creation of OpenUDID, co-founder Wayne Chang told me he believed it was not adequate.

“What we wanted to do was to address the actual reasons why Apple was removing it which was the privacy issue,” he said.

“We decided we wanted to do it the right way,” he continued, noting that the project falls under Crashlytic’s community initiatives, hence the open source license. “We’re not the only company that needs this type of solution.”

Chang is hopeful that mobile developers will embrace SecureUDID. Crashlytics raised $1 million from Flybridge Capital, Baseline Ventures, and a number of angels in October. For more on SecureUDID, read Crashlytic’s blog post.