Tip: Stuart Pomerantz, via Lifehacker
Ribbit Mobile is a voicemail and call routing service and competitor to Google Voice. Its new iPhone app provides voicemail transcripts, embedded call-back and SMS links and to-call list generation.
Lifehacker notes that in addition to having better transcription accuracy than Google Voice, Ribbit Mobile was allowed into the App Store by not offering in-app calling, SMS, or address book features. Google Voice was rejected from the App Store for bypassing Apple's Phone and Messages apps in favor of in-app communication — a no no.
On the other hand, Google Voice (for Android) allows you to hide your personal number and create a separate call-tracking list.