Using `new` would be old school (maybe even incorrect these days), but these definitely shouldn't be `init` since you'd never call them after an `alloc`. Something like `trackerWithMixpanelEventName:` could work here.

Also, as factory methods they should probably use `[self class]` instead of referencing the class directly:
https://developer.apple.com/library/ios/releasenotes/ObjectiveC/ModernizationObjC/AdoptingModernObjective-C/AdoptingModernObjective-C.html#//apple_ref/doc/uid/TP40014150-CH1-SW2