- Native iOS: Swift and Objective C - Native Android: Java and Kotlin - Cross-platform (iOS & Android): React Native - Cocos2d: cocos2d-x, cocos2d-JS - MEAN/MERN Stack (Node.js, Angular, React, ExpressJS) - PHP, Laravel, CodeIgniter - Databases like MySQL, MongoDB, DynamoDB, SQLite, CoreData - Wordpress - MBaaS like Parse, Firebase, etc. - Audio/video streaming, and processing - Text to Speech and Speech to Text, Text Recognition - 3rd party Social Network Integration (like FB, Google, Youtube, Twitter, Dropbox, Foursquare, Instagram, Tumbler, etc.) - Ad Network and Analytics Integration (AdMob, Flurry, Crashlytics/Fabric, etc.)