Using Lottie Animations in Expo Bare Workflow project.
Results of POC

Tested on Samsung Galaxy Tab A7 Lite

Implementation

react-native-lottie-splash-screen

The implementation of the react-native-lottie-splash-screen library was carried out without any trouble. The documentation is complete. However, it is worth noting that the library creates a confict with the regular expo-splash-screen library, so it should be removed beforehand

lottie-react-native

A bit worse is the lottie-react-native implementation for using animations inside the application. In the latest version 6.0.1, only the first frame is displayed. I spent about half an hour to solve the problem - to no avail. After downgrading the library to version 5.1.6, everything works correctly.

Performance tests

1. Startup time:

There is no tool for counting the app start time (from tap on the app icon to the disappearance of the splash screen), so I used a stopwatch and calculated the average time.

Type of Splashscreen	1	2	3	4	5	6		Average startup time (s)
Regular with PNG (expo-splash-screen)	4.27 s	4.42 s	4.22 s	4.37 s	4.45 s	4.27 s		4.33 s
With Lottie animation	5.58 s	5.35 s	5.43 s	5.23 s	5.2 s	5.21 s		5.33 s

Summary:

Application opening time with lottie animation was found to be 1 second longer (23%). However, it should be remembered that in both cases the application had a different set of libraries and assets, so the size of the application's bundle may also matter here.

2. Performance Using Lottie Animation in app

To measure the performance of the application, I used the RN Perf Monitor plug-in for the Flipper tool.

The results came out better than good, and the FPS number remained unchanged. Therefore, in addition to displaying the animation in a loop, I added a shitstorm function that changes the text color every 200 ms (thus clogging up the JS thread).

Summary:

Lottie Animation Results	Lottie Animation Results With Shitstorm	Shitstorm without animation

The statistics showed that displaying lottie animations at the same time does not affect the application's performance.

3. Memory usage:

We ran out of time, but for full performance tests, it is necessary to look at memory consumption as well.