3 month in saucer or jumper?

So my little guy is 13 weeks now, and is rolling over by himself and really wanting to sit up and stand by himself too... He has decent head control and is super strong in his legs ... Am wondering what the appropriate age is to begin putting them in things like exersaucers and jumpers ... I know they need good head control but how good does it have to be? Like he still needs my help to sit up and he still bobs his head but can lift it up completely sometimes ... Someone help lol