Question: Can you recommend a solution that provides prewritten code for features like authentication and in-app purchases to speed up development?

If you're looking for a template that offers prewritten code for things like authentication and in-app purchases to get you started faster, WrapFast is a good option. It's a SwiftUI boilerplate for iOS apps, but it's geared specifically for AI-powered apps. It comes with prewritten code for authentication, onboarding, in-app purchases and paywalls. It integrates with OpenAI Vision, ChatGPT and DALL·E for more advanced AI abilities, and comes with a Node.js backend, cloud database and analytics with Firestore and Firebase. It's geared for both experienced and new iOS developers, with documentation and step-by-step tutorials.

Another option worth considering is ROQ, a data and API layer that can be used to create multi-tenant, multi-role SaaS apps. It includes secure database queries, authentication, authorization and monetization features through Stripe integration. ROQ also offers managed Postgres database deployment, secure frontend DB queries, user authentication with social logins and 2-factor authentication, and AI-assisted data modeling with visual review and automated schema deployment. That can help you get to market faster with a much shorter deployment time of weeks.

For Next.js SaaS projects, Staarter offers a full-featured boilerplate with strong authentication and authorization, subscription management with Stripe, Paddle, or LemonSqueezy, and full localization support. It comes with an easy-to-use admin dashboard, payment management, usage limits, analytics tracking, and strong security, making it a good option for entrepreneurs and developers who want to save more than 50 hours of development time with a single lifetime access payment.

Backendless also offers a full featured solution for building high-performance apps with a low-code approach. It includes a visual UI builder, codeless logic for frontend, direct API integration, and real-time database capabilities. With streamlined user management featuring 18+ third-party authentication providers and customizable email and push notifications, Backendless offers flexible deployment options and integrates with a variety of third-party services. Pricing options range from free to paid tiers, so it's a good option for a variety of development needs.