Cloud Firestore

I am building a platform for a health provider using Vue.js with Cloud Firestore and Cloud Functions for Firebase. Some of the app features are: Video chat, Chat 1 to 1 Payment - using Stripe Mange clients - CRM

I am debating whether to stay with Cloud Firestore and Cloud Functions for Firebase as my backend (using ExpressJS) I built it in a way that will be easy to change to Rest API with other DB, but not sure if I want to keep using Firestore

I want to develop a mobile app with Cloud Firestore as backend. It's good until I realize need to implement FullTextSearch, and Firestore doesn't support it natively. Although they advise to use Algolia but at this time I'm not willing to pay for it.

Therefore, I'm thinking about using the built-in tool from Google Cloud. Since this app is online-only, the offline & sync are not a top priority, so how about use Google Cloud SQL? Or, do you recommend any stack for me? Thanks for your advice.

We are building a social media app, where users will post images, like their post, and make friends based on their interest. We are currently using Cloud Firestore and Firebase Realtime Database. We are looking for another database like Amazon DynamoDB; how much this decision can be efficient in terms of pricing and overhead?

I'm researching what Technology Stack I should use to build my product (something like food delivery App) for Web, iOS, and Android Apps. Please advise which technologies you would recommend from a Scalability, Reliability, Cost, and Efficiency standpoint for a start-up. Here are the technologies I came up with, feel free to suggest any new technology even it's not in the list below.

For Mobile Apps -

1. native languages like Swift for IOS and Java/Kotlin for Android
2. or cross-platform languages like React Native for both IOS and Android Apps

For UI -

1. React

For Back-End or APIs -

1. Node.js
2. PHP

For Database -

1. PostgreSQL
2. MySQL
3. Cloud Firestore
4. MariaDB

Thanks!

Could you pls help me to understand whether Cloud Firestore or MongoDB is better for rewards program

I planned to do a project in Cloud Firestore, which will store about 100GB of data. Shall I go for Cloud Firestore or traditional AWS RDS MS-SQL SERVER with AWS Lambda? Please I need your suggestion.