3 Practical Koin Dependency Injection Tips Every Android Developer Should Know

If you’re using Koin in a real Android or Kotlin project, chances are it’s already doing its job: wiring dependencies, keeping things readable, and staying out of your way.

But as apps grow, a few small DI decisions can quietly turn into performance issues, memory overhead, or runtime crashes.

In a recent video, Philipp Lackner shares three practical Koin tips that come directly from working on real-world codebases. 

And here's a summary of his tips

1. Use factoryOf vs singleOf intentionally — don’t default blindly

Many teams default to singleOf for nearly everything. It feels convenient — you declare a dependency once and reuse it everywhere.

But here’s the trade-off:

• singleOf creates a long-lived singleton.

• factoryOf creates a fresh instance each time it’s requested.

Why does that matter?

Consider use cases or screen-specific operations. These usually hold UI-related state and don’t need to exist beyond a ViewModel. If you define them as factories, they:

✔ live only as long as the ViewModel
✔ avoid global shared state
✔ reduce memory footprint

Singletons still have their place — databases, data stores, file systems, and HTTP clients are expensive to create and deserve a single shared instance.

Rule of thumb:

If an object is light and tied to screen or business logic, prefer factoryOf.
If it is expensive and broadly reused, choose singleOf.

2. Use the Koin IDE Plugin to Catch Wiring Issues Early

You forget to provide a dependency → the app compiles fine → it crashes only when the specific screen asks for it.

Large apps amplify this risk — more screens, more flows, and more paths nobody tests.

There’s a simple fix.

Kotzilla created a free Koin IDE Plugin that:

• visualizes your dependency graph

• highlights missing bindings

• gives you quick navigation to problem spots

Instead of waiting for a runtime crash, you can spot missing declarations directly in your IDE. Refresh the graph, scan for warnings, and fix before shipping — simple, but a huge reliability gain.

3. You Can Use Koin to Optimize App Performance

Because Koin knows your full dependency graph, it can help you understand performance bottlenecks.

The same plugin exposes Koin Insights, a dashboard that detects things like:

• slow dependency resolution

• blocking operations on the main thread

• overly complex dependency structures

It doesn’t just warn you — it explains what’s wrong and where to look.

• A ViewModel that feels slow to resolve? Likely doing too much work in init {}.
• A ViewModel taking six dependencies? Maybe too many responsibilities.
• A repository being recreated too often? Maybe switch factoryOf to singleOf.

There’s even built-in AI assistance that can suggest (or generate) fixes based on your actual graph — a useful starting point before refactoring.

We've published a sandbox so you can see for yourself with no setup required

Final Thoughts

Koin already keeps dependency management clean. With a few mindful choices like early error detection, and graph-based analysis — you can:

• reduce crashes

• simplify architecture

• improve performance