Midtrans does not directly provide official SDK for a hybrid mobile framework, because currently we focus on supporting native Android & iOS experience via our Mobile SDK. You can check the details of our Mobile SDK information here.
Rest assured, our payment products are compatible to be used on Flutter, React Native, or other hybrid mobile framework platforms.
The simplest and easiest method is to utilize webview (or similar method to display HTML page), the developer can display (via webview) the HTML page of SNAP payment (HTML which utilizes snap.js). So the developer needs to set up a web page that integrated with snap.js to display payment and use webview within the app to display it as a payment page.
Alternatively, the developer can also utilize Core API, which is JSON-based REST API, that should be able to be integrated on virtually any framework/platform.