Budget Friendly No-Code App Platforms

If you want to experiment with no-code app building, here are a few of the platforms that offer a free plan. Each of the "free" plans comes with limitations, but having done some tinkering on most of these sites myself, they are usually flexible enough that you can manage to build at least a basic version of the application you want to create:

• Open As App - You can have as public (available to everyone) apps as you want, but only one private (by invitation only) app and only one user for that app (for example, if you're developing an app specifically for another user).
• Caspio - One of the main limitations with Caspio is that their free plan only allows you to have five "data pages" in your app, where a data page refers to any form, report, chart, calendar - basically any screen that you display to a user.
  
• Bubble - No custom domain name, no CSV import or export.
• Zoho Creator - One app, no ability to use certain advanced fields.
• OutSystems - Only one "environment" (the area where your application runs).
• Unqork – No pricing information available.
• Tonkean – Has a “sandbox” free trial with 1 day data retention.
• Thunkable – You can develop Android and iOS mobile apps for free on Thunkable. All your apps will be public however – to make your app private you have to have pay for a “Pro” membership ($25/month). Note: You also have to pay a small percentage of your earnings if you use Stripe to accept customer payments.
• Adalo – Adalo has a free “Explore” plan. You can create an unlimited number of apps, but you have to publish to an Adalo domain, your app will have Adalo branding, and you're limited to 50 rows of data per app.
• Budibase – The Free version of Budibase allows you 1 app, 5,000 total records, 3 data tables, 3 views, 500 MB of attachment storage, and 100 automation runs per month. “Automation runs” refers to business automation processes (running processes automatically that were previously done manually) and to integrations with third party apps.
• Quickbase – Quickbase has a 30-day free trial that includes the platform's main features: workflow automations, data and app integration, and the ability to create unlimited mobile-ready applications.
• Quixy – Quixy's free trial includes all of the platform's core features.
• Kissflow – No free plan and no free trial.
• Mendix – The free plan on Mendix allows you to create no-code or low-code apps with 2 environments per app (where an environment is a deployment site).
• AppSheet – You can use the free version of AppSheet as long as you want in order to develop prototypes. However you can't actually deploy the apps you develop.