I'd pay good money for an iOS version. I'm limping along with Threema now (which, functionally, is really great!).
I'd pay even more good money for hosting to not be in Google's data centers.
I'd pay even more good money for hosting to not be in Google's data centers.
The TextSecure servers are not hosted in Google's data centers. Google's GCM push messaging framework is used to deliver messages to Android users, but the GCM payloads are fully encrypted.