Appcelerator Titanium

First and foremost, there's Appcelerator Titanium. This versatile platform is ideal for developing iOS and Android apps, and comes with plenty of built-in tools and features to make it easy to get started. Plus, Appcelerator offers a wide range of subscription plans for individuals and businesses of all sizes.

Amazon Web Services (AWS)

If you're more interested in Amazon Web Services (AWS), then you'll want to check out Lambda. AWS Lambda lets you run code without having to specify details about the deployed environment, making it perfect for prototyping or testing purposes. And because AWS Lambda runs completely in the cloud, there's no need to worry about hosting costs or infrastructure setup - it's totally free!

Google Cloud Platform (GCP)

Another great option for mobile app development is Google Cloud Platform (GCP). With GCP, you have access to powerful infrastructure resources like storage, computing power, streaming services and more. Plus, GCP offers a wide range of developer kits and tools that make it easy to get started with coding. 

Mobify Octane

Mobify Octane is another popular tool that boasts powerful AI capabilities for mobile app development. The Mobify Octane platform can be used to speed up the process of designing and building mobile apps, by helping developers with different tasks like user research, data tracking, and A/B testing.

Auth0 Social Login

Auth0 Social Login is a social logins tool that uses artificial intelligence to help users sign in automatically with their Facebook or Google accounts. This ensures that your users never have to fill in any personal details again when signing in to your app or website.

Apiwire

Apiwire is an Artificial Intelligence development platform that helps developers automate the tedious parts of mobile app development like user profile creation, authorization flows, and notifications management. This ensures that your apps are properly built faster and with less hassle.

And finally, if you're looking for something more specialized but still versatile enough for mobile app development, then look no further than Microsoft Azure Mobile Apps. Azure Mobile Apps provides industry-leading capabilities such as Scalability up to 10 million active users within minutes, Unrestricted data sizes up to 1GB per user per day, Built-in global fleet management capabilities via Workspaces Expressions and ExpressFX Add-ons Suite – allowing your organization increased agility across applications from end-to-end.