Apple's controversial replacement of Google Maps with its own in-house mapping solution may have left some users scratching their heads, but journalists at AllThingsD believe they know why: the absence of voice-guided, turn-by-turn directions.

Android users have been enjoying GPS-like navigation through Google Maps for some time now. As it turns out, Apple wanted it to, but the big G wasn't about to hand over one of its key smartphone advantages for free. Purportedly, this is where negotiations broke down. Google and Apple discussed the inclusion of voice-guided directions in iOS, but an impasse was reached after being unable to conjure up a mutually beneficial compromise. Google asked Apple to do things like brand iOS Maps app with "Google" or add features like Google Latitude in exchange for voice navigation, but it seemed as though Apple wasn't willing to play ball.

When Apple saw talks to include voice navigation unraveling at the seams, it began acquiring fledgling companies like Placebase, C3 and Poly9 for their mapping technologies. These acquisitions helped fuel rumors that Apple was indeed working on its own home-grown mapping solution – something we now know to have been true.

Apple is used to having tight control over its products and services. Having its archnemesis in mobile, Google, in the driver's seat made Cupertino very uncomfortable, sources from AllThingsD explain. 

Interestingly, The Verge recently noted that Apple may have launched its Google Maps alternative more than a year before its contract with Google actually expires. Given the criticism engendered by Apple's less-than-perfect foray into the mapping arena, the company's hasty attempt to distance itself from Google may have been fueled by that discomfort.