iOS and Android may be the bigger platforms for now, but probably not for long. Windows is huge, around 90% of the PCs and laptops around the world runs it. I think there will be over a billion devices running Windows 8/RT in a few years.
Developing for Windows 8 now is really smart: there are only 43.000 apps at the moment, meaning that there is very little competition. If you start building a Windows 8 now, you are a huge leap ahead of the competition.
"there are only 43.000 apps at the moment, meaning that there is very little competition"
The numbers get even more interesting when you move into some specific subcategories: according to my version (UK) of the Windows Store, there are currently ~230 action games, ~550 arcade games, ~180 card games, ~80 shooter games and ~60 simulation games on it.
I doubt the numbers for the US and other versions of the store are very different, since basically nobody will restrict themselves to only the UK market if the game is already in English.
Now, I don't know any statistics on how strongly users depend on using subcategories to find games, but I know that's what I'd do if I wanted to find an interesting game.
As you can see there are only 111 'government' apps for example. Since the list of 'top x apps' only contains 100 entries, you're pretty much guaranteed to be in the top 100 of government apps when you make one (it can be anything, an app for a political party, an app for polls, etc.). The same goes for 'shopping' and 'security' (and a little bit for finance, which has 360 apps).
Edit: here are the stats for the different 'games' subcategories:
I'm betting there will be a fairly sharp increase in the daily submission rate for games once Unity3D makes deployment to the Windows Store available for everyone. According to the Unity guys, they currently have 'no information' on when that will happen, but since some of their selected partners already have this option I'm guessing it'll be a matter of just a few months or so.
Avalaxy you basically summed up my thoughts behind choosing Windows 8 to start. Of course I get strange looks whenever I tell other developers what I'm doing. If you are interested you can read my full thoughts complete with some numbers: http://spottedzebrasoftware.com/blog/ignore-windows-8-at-you...
It may not come as a surprise, but I am currently interning @ Microsoft (Netherlands), doing research into the Windows Store vs the competition (Play Store, Apple App Store) to find out where the opportunities for developers/marketeers/entrepreneur in the Windows Store lie. I've got some interesting numbers, there are more opportunities than one might think.
I agree Windows is an interesting target. Best thing is to target multiple platforms at the same time though. Many people might think this is a lot of work, but I don't think this is necessarily true.
I've recently began rewriting our framework to Mono / C# and so far it's been a good experience. From what I've read I should be able to have at least 50% shared code across platforms, but some type of apps can perform even better. Games written with MonoGame (open-source version of Microsoft's XNA framework) might be able to share over 90% of the code between iOS / Android / Windows Phone apps. Also the Ubuntu phone will be a possible target in the coming year.
So yeah, I agree Windows is an interesting target, but you don't want to miss out on the other markets. Mono is the best solution to have a performant app for most platforms while at the same time offering a native UI experience.
I used MonoGame for Adlib and Petunk. For Windows 8 and Windows 7 the games share almost all of their code. I would estimate 90%. The only differences are persistence, sharing, that sort of thing. That said, it gets trickier when you want to create complex user interfaces or support different resolutions. In fact for my latest game I've switched to XAML completely due to those problems.
The most important thing, in my opinion, is to follow the MVC or MVVM (my preference) pattern and keep all of your game logic in a portable class library. This will give you the flexibility to target new platforms relatively quickly in my experience.
I've made a number of solutions to common problems I ran into which run on Windows 8 and 7 (and potentially other platforms) available if you're interested. Check it out here:
Here's a freebie: fix sort by rating. Currently the Windows store does a simple average. This means all apps with a single self-awarded five star rating dominate the rankings.
Sorry, my previous post may not be clear. I'm doing research into the store as in 'the available apps in the store, what kind of apps are popular, etc.', not the store itself :)
This pretty much confirms my hypothesis that Microsoft employees just don't use and/or care about their own products.
The product is undeniably broken, and you work on that product? Aren't you at all concerned about having the problem fixed, even if it is not directly under your control?
Wait, what? That is one very strange conclusion. I didn't apply for a programming internship at Microsoft, it's a market research internship. I don't even have access to the team that developed the Windows Store... So no, I don't work on that product.
These PCs and laptops are the very same machines that "apps" users are deciding they just don't need any more. Full desktop applications for Windows aren't going to go away, but as I see it they're not going to be ported to "So modern we can't agree a sensible consumer-facing name for it" rapidly, either.
I agree that it's a good place to be selling right now, as the competition is sparse and largely terrible. There are a lot of holes waiting to be filled. I don't think it's going to grow the way you seem to be predicting.
Developing for Windows 8 now is really smart: there are only 43.000 apps at the moment, meaning that there is very little competition. If you start building a Windows 8 now, you are a huge leap ahead of the competition.