Why Should You Care?

Making your app offline-first is essential if you want to provide the best user experience. It makes your app significantly faster by reducing the number of network calls, which in turn also reduces server costs.

What does Offline-First mean?

The core idea is to persist/store remote-fetched data on the device. This allows users to access the data instantly, skipping unnecessary network requests—until the data expires or is invalidated.

If your app has this feature then your app is offline-first if it does not then lets make it one.

While offline-first apps come with some complexities, the benefits far outweigh the challenges. but before we start a small disclaimer.

A Quick Disclaimer

There are multiple ways to approach offline-first implementation. What I discuss here is my approach, tailored to my requirements. There might be better methods for different scenarios so take these as suggestions and not rules.

If you have suggestions, feedback, or alternative approaches, I’d love to discuss them! Let’s learn and refine this together. As I explore further, I will actively update these articles with new insights/approaches/strategies.

Now, let’s get started. 🚀

Offline Strategies: Partial vs. Full Offline Mode

There are two main strategies for implementing offline-first functionality:

  1. Fully Offline Mode
  2. Partial Offline Mode

The main difference between them is whether the user can modify their data offline.

1️⃣ Fully Offline Mode (CRUD Operations Offline)

In this approach, users can:
✅ Create, Read, Update, and Delete (CRUD) without an internet connection.
✅ Sync data to the cloud when online.

🔴 Major Challenge:

  • If a user forgets to sync data from one device (e.g., a tablet) and later accesses their account from another device (e.g., a phone), they might think the data is lost.
  • This can frustrate users, leading to complaints or abandoning our app.

🔵 Idea Use case:

Best option for apps that does not support multi user and has single device login, but ⚠️ The data loss % is still significantly high if user forgets to connect online after the initial login and loses his device etc, but thats a tradeoff you have to live with.

While this approach offers true offline functionality, it introduces complex synchronization issues, making it harder to maintain data consistency across devices.

2️⃣ Partial Offline Mode (Read-Only When Offline)

In this approach, users can:
✅ View/Read data offline.
❌ Modify data (Create, Update, Delete) only when online.

🔹 Why We Chose This Approach:

  • Multi-device users won’t face sync issues since data is always available in cloud.
  • Less complexity & better error handling & almost no possibility of data loss.
  • Data remains clean and consistent with the server.

🔵 Idea Use case:

Best option for most use-cases simple or complex or extremely complex data set apps, with or without multi-user or multiple-device-logins and what not.

This is most preferred due to its data-consistency point and much simpler to implement, Now checkout the next one.

3️⃣ Hybrid Offline Mode (Partially-restricted Write operations)

The Hybrid mode is using both discussed strategies depending on the use cases, for example you may allow the user to update their profile details or personal notes etc but not the public contents that can cause issue with other uses on the same org/team.

✅ View/Read data offline.
✅ Modify some data even if offline.
❌ Modify most data only if online.

🔵 Idea Use case:

Best option for most simple or complex apps, with or without multi-user but strictly allow only single-device-login, this enables the user to do write-operations to user specific data while restricting the same for other parts of the app, there are tradeoffs here as well but only a particular user will be affected in the org/team.

For me the partial offline mode stands out as best option and would suggest the same for most use-cases, we will be sticking with this through out this journey.

Now, let’s dive into how we fetch and synchronize data.

Data Synchronization Strategies

Once we are decided on partial offline mode, the next question is:
👉 How do we fetch data from the server and keep it updated?

There are two main synchronization approaches:

1️⃣ On-Demand (Pull-Based Synchronization)

  • Data is fetched only when the user requests it.
  • Data is invalidated when it expires or is manually deleted.
  • Lightweight & user-centric—fetches only relevant data.

2️⃣ Clone (Push-Based Synchronization)

  • The local database mirrors the entire remote database.
  • Auto-updates when the server sends a flag indicating it was modified.
  • Heavy & resource-intensive, as it may download unnecessary data.

🔹 Which One Did We Pick?
We chose On-Demand Synchronization since it’s:
✅ Efficient (fetches only what’s needed).
✅ Faster & lightweight (minimizes unnecessary data transfers).

However, we use mox of both lets call it a hybrid approach, we loaded some data that user will need on the navigating screen to ensure a better user experience. After that, everything is strictly on-demand the data is synced only based on user.

Which Local Database Library Should You Choose?

There are several local database solutions available, but we chose Google’s Room Persistence Library. Here’s why:

✅ Built on SQLite – but with a modern, developer-friendly API.
✅ Works seamlessly with Kotlin (supports data classes).
✅ Compile-time SQL query verification (reduces errors).
✅ Built-in support for LiveData, Flow, and Paging.
✅ Faster development (less boilerplate, easy migrations).

Using Room significantly accelerates development while maintaining a structured and reliable database. It’s my go-to solution, and I highly recommend it for Android and Kotlin Multiplatform (KMP) projects.

What’s Next?

This article laid the foundation for an offline-first architecture and explained why we chose partial offline mode & on-demand synchronization.

📌 In the next part of this series, we’ll dive into:

  • Setting up Room in an Android.
  • Exploring Key Components of Room.

Final Thoughts

This is my journey in building an offline-first app. I’d love to hear your feedback, suggestions, or questions!

Feel free to connect with me on:
📩 Email
🌍 Website
💫 LinkedIn-Post for comments and feedbacks

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