Not yet. This is a planned feature but the implementation has not been decided yet because this feature is not exactly compatible with how Tox works and it could cause a lot security issues.
Not any time soon, as iOS isn't very FLOSS friendly (in fact, the GPL is not compatible with the Apple app store). There have been talks of making a licensing exception, but the iOS client with the most progress (https://github.com/Jman012/Toxicity) isn't functional at the moment.