Apple has admitted that its Messages app still has unresolved issues and promises that a fix is coming in a future update. The problem is manifest when switching between using iMessages and text messages, but the system has also been plagued by server-side issues.
I use iMessages for everything and I have experienced a number of issues when dealing with text messages. I was recently in an area with poor signal quality and my iMessages were getting stuck while sending. You can hold on the message for more options, which includes the ability to send as text message, but the reliability of the system plummets when mixing text and iMessages.
I also have tried to use the Messages app with iMessages turned off on my phone. Within about 30 minutes I had friends calling me asking why their texts weren’t being received by my phone. While I’m not sure if this is directly related to the bug, it points towards a systematic problem within iMessages.
Another issue is that it is hard to navigate between the different devices and connection options. The Messages app on my laptop is currently set to receive when people send to my email address but not my phone number. My phone is set to receive on my email address and my phone number. A friend of mine shows up on my phone and laptop when he sends to me but if I send from my laptop he wont receive any of the messages. I ended up setting all devices to receive on all options and that seems to work the best.
The primary bug that Apple is planning on fixing has been around since 2011 and exists when an iOS user switches to a non-iOS device and tries to text. It is possible to turn off your number in the iMessage system before switching but if this isn’t done, then that is when the Apple iMessaging system hijacks the messages. The bigger problem still exists, however, that when connecting multiple devices together using multiple systems of communication, there are still issues in connecting and communicating.