I wish to open up my PHP website to Android, iOS and Windows 8/Windows Phone.
I’ve been looking at the library for PHP SOAP and I’ve got it working.
Although I’ve done this, I’ve seen people posting online that SOAP is “outdated”.
Is it, and if so, what are the alternatives?
SOAP is usually quite “heavy” when designing and consuming and it’s based on XML. For a more lightweight approach you might want to look at REST-style APIs that are easier to implement, adopt and can purely be based on JSON which makes it easy to consume those services with Javascript/Client side technology:
https://en.wikipedia.org/wiki/REST
There may be good use cases for SOAP though – but I figure you’ll find those mainly in heavy enterprise applications.