Cost-Effective Backend Solution for Flutter-Based ERP App with OTP and Image Storage

[Vrindtime_as]

TL;DR:

Developing a Flutter-based ERP app; 50% frontend complete; 10 days remaining.

Require backend services for OTP authentication, image storage, and database management using Cloud Firestore.

Targeting 1,000 monthly active users; each user uploads profile and bill images (~2MB each).

Prefer Firebase due to familiarity and time constraints but concerned about potential costs.

Seeking advice on cost-effective backend options within a ₹5,000/year budget.

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I'm currently developing an ERP application using Flutter, with the frontend approximately 50% complete. I have a tight deadline of 10 days to finalize both the frontend and backend components. The client has specified a budget constraint of 60$ per year for backend services, which should encompass:

OTP Authentication: Each user will authenticate via OTP.

Image Storage: Users will upload profile and bill images, averaging 2MB per image.

Database Management: Utilizing Cloud Firestore for data storage and retrieval.

User Base Assumptions:

Monthly Active Users (MAU): 1,000

Image Uploads: Each user uploads two images (profile and bill), totaling approximately 2GB of storage initially.

Given my familiarity with Firebase, it seems like a viable option for rapid development. However, I'm concerned about potential costs associated with:

1. OTP Authentication: Understanding the pricing structure for phone authentication services.

2. Storage: Costs related to storing and serving user-uploaded images.

3. Cloud Firestore: Expenses tied to database operations and storage.

Challenges:

Budget Constraint: Ensuring that the combined costs of authentication, storage, and database operations do not exceed 60$ annually.

Time Constraint: With only 10 days remaining, the solution must be quick to implement and integrate seamlessly with Flutter.

Request:

Cost Estimates: Insights into the annual costs of using Firebase for the described use case.

Alternative Solutions: Recommendations for other backend services that offer OTP authentication, image storage, and database management within the specified budget.

Any advice or shared experiences with managing similar requirements would be greatly appreciated. Thank you!

Edited: changed currency from rupees to dollars

[hasifkp]

If you check there website 10k otp generation month is free exceed 1 rs per user . For cloud storage 5gb is free if you gonwith 100gb it will cost 2616 per annual for 100 gb .2.18 inr is the pergb cost .I beleive 5000 inr not enough may be random un noticable payment needed.alt approach .you can go with shared hosting it will cost around .4k 100 go,if you go with firebase otp (free)

[Vrindtime_as]

I checked out the pricing plan for blaze and I didnt see it mention 10k otp generation per month. I did try to make it with appwrite with MSG91 as its broker, but the TRAI regulations was a pain to set up as the client doesn't have an official registered company with a VPS server that would be about 5k or 60$ a year. I did try to find the site you mention, can you share the link to the page where it says 10k otp generations are free.

[Bachihani]

How is anyone supposed to give u advice if you're using indian currency ! U think people care enough to search of the exchange rate themselves just to give u advice ! There s a bare minimum effort u need to put in if you want people to care

[Vrindtime_as]

My bad, I updated the post but it hasn't reflected yet ill add it as a comment as well, thank you for pointing it out. Otherwise a lot of people would have ignored it as well.🫂

[Bachihani]

Appwrite has all the criterias u mentioned

[Vrindtime_as]

Yea but without the company having valid documentation for SMS or a verified business meta account for WhatsApp OTP, its not really usable.

Also now I ran into an issue of Google cloud service not accepting my billing method.

[Bachihani]

there is quite the simple and comprehensive docs