Some people have been wondering whether new app stores like Aptoide on iOS will be successful. My initial reaction is that First Mover is really hard to overcome. It's even harder if the rival you want to compete with has had years of headstart on you and built up a market-dominating position. It's hard to imagine any social network readily dethroning Facebook when they have literally billions of users, and a primary goal of a social network is "I can find and talk to many/most of my friends on there".
In the case of Aptoide, they're up against a company that hasn't just had dominant market share, but a 100% monopoly, and they've had it almost 16 years now! They have over six million apps available - more than you could explore in an entire lifetime. Most of which are free to download. Typical users will look at a new app store and ask "what problem does it solve for me, or what new thing does it offer that I don't already have"? They're likely to think "not much"! Existing app developers & publishers aren't likely to see much reason to even put their apps on alternative app stores, and even an app that's on both, people will probably download from the one they've been using for years rather than download and learn something new. It's a very "big lift" for a company to try and break in to such a long-closed market.
To get an idea HOW heavy a lift it is, look at the Windows gaming market, where Steam has held a dominant market position for a comparable length of time. Currently they have around 75% of the market for PC games. Epic Games decided to try to break their near-monopoly and try to make the market competitive enough to reduce distribution fees charged to developers & publishers from 30% down to 12%. (A footnote here - when I started in the 1980s, a freelance game developer could typically get 4% to 12% of the retail price of a game, once the brick and mortar store too their 40%, a distributor took 20%, and your publisher took 28% to 36%. The fact that instead of 4-12%, we're now fighting to boost our 70% share to 88% isn't something I lose sleep over - instead I think what a fantastic time it is to be an indie developer or own a small game company!)
Epic decided to fight their way into the online game store for PC market by throwing around cash to 1) Get some exclusives on new games (typically for the first 6 months or so), and 2) Give away one or two quality games to their users every week. How much does this cost them? Do they negotiate some discounted rate with the publisher in exchange for getting them more copies "sold" than they would have if users were already paying?
No. Epic pays the game publishers the FULL retail price of the game for EACH copy players get for free. Basically Epic is buying millions of players these games at full price.
Of course it's an effective way to build market share. A number of gamers will go once a week to get free games - not little app store type games either, games that may sell for 20-30 dollars or more, some of them AAA games.
How much does this cost Epic? Literally billions of dollars a year. They have committed to losing billions upon billions of dollars for 5+ years to build market share, in hope that eventually they can have enough market share to move towards profitability. The fact that they own Fortnite, which is sort of like having a money printing press, enables them to try this option.
Will they succeed in the long run? Nobody knows yet. But they might.
This is the price of breaking into a mass market where a huge corporation dominated. In this case the 3rd largest market cap on earth, and the difference between them and the top 2 is basically rounding error right now.
Does Aptoide have billions to spend to buy their way in? Or even hundreds of millions? It's hard to imagine that "mere" tens of millions would make a dent, if they even have that much.
Will alternative app stores matter on iOS eventually? Maybe. But they'll have to come up with some crazy innovation, or spend a mountain of cash... Or swarm around like minnows around Godzilla's toes until one day some crazy indie developer makes a mega-hit game that they chose to release on one of the baby app stores only, and people take notice. But I wouldn't gamble on it.