In the US, it is typically after 9 months that it is recommended. Riley has excema flares that are definitely made worse by milk, although not yoghurt specifically. Since your lo is still so young, and you have that excema issue, I would definitely wait. It can be quite filling, and at this age, you don't want him to substitute it for bm.
If you want other foods to try, start considering some finger foods if you have not done any yet. Check out the BLW thread for other Mom's experiences.