Here is a collection of links to the websites and tools that I used for creating and marketing my games. I promise to regularly update the list if I find something smelling useful.
Tutorials
Ray Wenderlich’s Site – a collection of tutorials on all aspects of iOS game development.
Graphics
Font Awesome – a free font with awesome icons.
Da Button Factory – a place where I prepared buttons for my game. It’s much easier and faster than drawing them myself.
Cool Text Graphic Generator – an online tool to generate cartoon-looking text. For example, flying “+1” bonus.
Orname – free vector ornaments. I used them for Greek Letters and Alphabet app.
CG Textures – free textures in high resolution (there is a daily limit for downloading). I experimented with them as backgrounds for my apps.
Charbase – tables of special characters where I found arrows for Greek Letters and Alphabet: “Σ ↣ S”.
MakeAppIcon – a generator of icons of all sizes required for iOS from an 1024×1024 image. Just feed your graphics to their toaster and wait for an e-mail with icons.
Icon Slayer – another generator of icon library based on the 1024×1024 image. Not yet supports iOS7 icon sizes.
Sounds and Music
MuseScore – free software for entering sheet music and converting it into midi and mp3 files. It’s quite useful for my plans to incorporate classic compositions into my apps. Not all music that I like is available as public domain recordings.
3000 Royalty Free Sound Effects – a pack that I bought for my apps ($37).
Classical Piano Midi Page – a great collection of midi and mp3 classic music files (© Bernd Krueger) available for free with the attribution license.
Marketing
SensorTower – an interesting resource where one can play with keywords. I wish I found it before launching my first game. Extremely useful. They also have an interesting blog about marketing apps.
App Annie – a well-known analytics website where you can learn quickly how your game doing in top charts. Registration is recommended.
App2Top – a collection of news about app marketing (in Russian).