At the moment, Freetrade plans to make money in four ways:
- Charging users who want to make instant trades
- Charging users for Alpha subscriptions & people who want to use ISAs
- FX fees
- Earning interest on users uninvested cash balances
You can see their pricing here.
In other words, despite having a business model that enables users to invest for free, unlike the challenger banks, they have a business model in place that will enable them to make money from day one 
They won’t make money on hidden / opaque charges like spreads or commissions, which will be an important factor when it comes to earning user’s & potential user’s trust.
Providing the types of services that day traders typically want like leverage, options, short selling etc. is not a good way to build a sustainable business in my humble opinion. You end up with customers who lose all of their money, which means they won’t come back & the chances are, they’ll tell their friends to avoid your service too. I personally don’t like the ethics of those businesses.
But fortunately, there is more than one way to make money as a broker without doing that sort of thing. Freetrade want to encourage long term investing which is good for them & their users.
I’m optimistic that this ethical approach will make the media much more willing to cover / promote their service & users to recommend them to their friends. And that ultimately they’ll help change the narrative from investing being for the wealthy or essentially adrenaline fuelled gambling, to a mainstream practise, that’s considered as sensible as buying property is right now.
@Ronan is right that Freetrade won’t be offering options either.