Not trolling??? Your comments add nothing to the OP's original query. Your implication being he/she needs to buy an iPhone in order to solve their problem wasn't a practical solution, nor is it even a solid fact. Suggest you go to a local Apple Store, sit there, and just listen to some of the issues the Apple Genius staff are solving for the customers. Here in the real world, there is no service in existence that's fault-free with a 100% record of uptime. Also, there's no iMessage version for Android and despite the often misleading claim that pops up frequently in the rumor mill that one is coming, Apple has made it clear it has no intention to do so. It's business plan is about enforcing its vendor lock-in on a loyal, captive sector of the population, and it's accumulated a huge amount of wealth that way. Opening up its iMessage app to be more seamless with SMS/MMS, or even support RCS, would be a public service but Apple isn't a social services kind of corporation.
Implying iMessage as some sort of solution to a Galaxy S8 texting issue is indeed trolling.