Are you looking for free and best android & iPhone app building services ? If you want to launch your own mobile app free of cost, these app builders can help you to make launch your own app without coding.
Some of these app making services also allow users to monetize their apps for making money. If you also want to make money by promoting your own Android app or iPhone app, check out these useful services. Although all of these services cannot be used totally free but most of these sites offer free services for internet users.
1. AppGeyser ( Android App Builder ) - AppGeyser is one of the best android app builders that helps you create your own android app without coding. The site also allows users to make money by promoting their app. AppGeyser monetizes your android app with high paying ads so that you can make money by promoting your app on the web. The method is very simple, just visit the site and create your own app and start promoting your android app to make money with ads.
Very useful service that helps users make their own mobile app without any technical skill. You can also add many features to your app such as social sharing option, messaging, tabs and many other useful functions. AppGeyser also helps you to distribute your android app through AppGeyser android app marketplace. 
2. TheAppBuilder ( iPhone, Android, Windows ) - One of the most popular mobile app building services on the web that allows you create free web based mobile apps.You can also create native apps by upgrading your membership. Very useful site that offers easy app creation tools which can help you build your own iPhone or Android app for professional or personal purpose.
If you wish to make money by selling your own mobile app,you can upgrade your membership to create native Android or iPhone app. Free membership has many restrictions so it cannot be used for money making purpose. Theappbuilder offers many features including user friendly app toolkit, multiple mobile platforms and public distribution option.
3. Infinitemonkeys ( iPhone & Android ) - Fully functional app builder that helps you make awesome android and iPhone apps without few minutes. The site also helps you to publish your apps to app stores free of cost, but if you want to make money from your app, you have to pay small fees. The site offers easy tools to create web and native apps for android and iPhone devices. 
4. Gamesalad ( iPhone, Android, Windows & Mac ) - Gamesalad is one of the best and popular online services that helps you make your own mobile or desktop games. Although you cannot access all of useful features free of cost. Although you can create fully functional addictive games for all platforms free of cost but if you wish to make money by selling your games, you have to pay money to Gamesalad. Very useful app builder for game developers.
5. BuzzTouch ( Android & iPhone ) - Full featured free iPhone & Android app maker that allows you to create easily mobile apps, download the app source code and launch them to Android or iOS app stores. BuzzTouch also offers many tools and plugins that can help you make your own app with ease.
6. Appsbar ( Android , iPhone & Facebook ) - Very easy to use app builder that allows you to create android, iPhone, Facebook and web apps. You can use this useful service free of cost. Very useful service to create beautiful , featured rich and user friendly mobile and social apps.
7. Appypie ( iPhone, Android, Blackberry & Windows ) - Appypie is one of the fastest growing DIY mobile app builder that lets you create featured rich app for almost all popular platforms such as Android , iPhone, iPad, Windows & Blackberry. The site offers easy drag and drop tools app creation tools that can also be used by non technical internet users.
8. Andromo ( Android ) - Andromo is one of the best places to build fully functional native Android apps free of cost. The service helps you make your android app without coding and you can also publish your app on Android app store to make money with your app. Although you cannot access full features with the free plan but free plan also helps you create free app. For more pricing details, you can view their pricing page.
9. AppMakr ( iPhone, Android ) - Great free mobile app maker that helps you build your own Android or iPhone app without coding. You can create easily your mobile apps using this service.The service also allows you to make money by monetizing your own apps.
10. iBuildApp ( iPhone , Android ) - Popular free web service that allows internet users to create Android and iOS apps free of cost without coding. Very useful service for non technical internet users who want to make their own mobile apps. The site offers easy app creation tool with many features such as tools, social features, analytics, notifications, ad revenue option and lots of other features.