Free Stocks

Freetrade

Freetrade offer commission-free trading via there app. They do have a range of ETFs/bonds/US stocks as well as UK and European shares.
They also offer Fractional shares for US-based stock so you can invest in a company at a level your happy with.

They currently are offering Free shares up to the value of £200 for new accounts via the link below

 

Coinbase

If your looking to expand your investment portfolio and are leaning towards cryptocurrencies Coinbase would be your best bet.
There currently offering £7.21 worth of bitcoin when you buy £72.1