Forstall: We did not want the carriers
According to Forstall, who even in 2013 Apple as iOS boss in the fight had to leave , but the company still appreciates , there were, among other difficulties to expand the existing standards. In addition, it was not possible to establish interoperability between the then-to-be-changed SMS system and the mobile service providers. And especially important: The carriers wanted to continue to earn money with SMS and – according to Forstall – “a significant flow of revenue”.
The result was, after all, that Apple has kept its service proprietary until today – to the chagrin of users who are (also) moving in the Android world. iMessage basically only runs on Apple hardware, which also applies to the end-to-end encryption used. If you want to reach Android users, you have to use the regular (and comparatively insecure) SMS or use external services like WhatsApp. An iMessage version for Android Apple has never made and will probably never do it according to their own previous statements.
On iOS devices, there is a strict separation between SMS and iMessages in the news app: messages from the Apple service are displayed in blue, text messages in green. Some iPhone owners unconsciously limit friends with Android phones – so additional features in iMessage can not be shared with them, such as animations. According to Forstall, Apple has always been concerned with making sms better: simple text communication should have felt “more like a conversation”.
Attempts by mobile operators to implement their own SMS successor, have so far failed on a broad front. Services such as the Rich Communications Service Protocol (RCS) with the carrier’s own apps were barely successful, while the use of SMS (and its revenues) is shrinking.