Save and write to text or csv file

[Still-learning (1-2-3-4...)]

Have you checked this extension?

[F/OS] SharedDB - Store / Retrieve data between applications

SharedDB Shared db uses Shared Preferences in WORLD_READABLE mode which can make another applications read the data. For example if you store a value in Application1. It can be accessed ( Read only ) by Application which is not possible in normal Preferences. This extension is discontinued and won’t be getting any updates in the future. Notes Do Not use to Store Confidential/Important data in this DB. Other applications can also read the data. ( If you are storing information like this, …

Else why don’t you try some online storage applications like gsheet, baserow, airtable?? It depends upon your expectation…