No, I would never use Expo for a serious project. I imagine what ends up happening in most projects is they reach a point where they have to ultimately eject the app (e.g. needing a native module) which sounds very painful.

The majority of the apps I've wrote have definitely reached that point, for the individual benefits expo provide (e.g. code push) I've considered trying out using just expo kit but I'd rather just uses a tool specifically for that purpose. Above all, I always like to reduce the level of magic in any application, mobile or not.

Regarding "What package do you recommend for UX", I guess it really depends what you mean. But hopefully this gives you everything you need to know:

• For navigation I use react-native-navigation, can't recommend this enough as it adds a massive difference in fidelity vs using JavaScript based lib like react-navigation.
• For interactive elements (drag drop, sliders, parallax etc) I use a forked version of react-native-interactable.
• For custom vector animations e.g. button icons I use Lottie.
• I do not use a framework for developing styles/grid layouts (e.g. glamourous), I've got my own base-layout of styles and components.

This is a really good question, in a meeting at the moment but will definitely respond to this!

If you haven't moved to RNN v2 by now, I'd recommend it ;)

I solved this problem.. If you wish to know ? Ping me

Hey Faiz, were you able to solve this issue? could you please elaborate on what package you used for handling push notifications?

The only case I've seen that can be tricky to keep performant at the moment is when you're doing CPU heavy tasks whilst listing out uncompressed images >2mb. Memory consumption of images this size do seem to be a tricky problem, though libs like react-native-fast-image aim to solve this sort of thing.

I'd say almost certainly they were developed badly, there's no reason now why you couldn't make apps indistinguishable from native. My top tip for this is to move away from JS based navigation libraries (e.g. react-navigation), that's where you see a lot of the performance gains.

Performance wise the Patient View app I made shows this off, I sync and encrypt thousands of records and chart them out whilst keeping everything 60fps.

1 - Upgrading projects from very early versions of React Native. This has been, at times, an absolute nightmare (mainly iOS)! Especially when your project relies on several libs that require native changes. In the end, it was often easiest to create a new react native project from scratch and manually link libraries one by one.

Thankfully, this is rarely an issue now as it has matured. Having said that, I think it's really important to stay on top of React Native versions if your project has longevity.

2 - I had to integrate a react native app to read sensors for a car HUD, no simple way of overcoming this I just had to learn Objective C to write a React Native Bridge. Getting comfortable doing this is really valuable if you run into projects that require specific native functionality.

3 - Once, I hit an error which I could only replicate at the point of uploading a react native app, it would error out with "You must supply a CFBundleIdentifier for this request". This had me banging my head against my desk for a few days. In the end, it was something simple like the way I was creating my release scheme in xcode.

Good question and congrats :).

How hard much harder is it, to publish both Android and IOS, vs just IOS?

To get the last question out of the way, I'd say if you face any red tape it's almost certainly going to be on iOS side. Also the time bottleneck is going to be iOS side too, publishing can take 1-2 days but sometimes more.

What should I be prepared for when publishing my app?

I can't give you a simple one sized fits all answer here, but I would say that as long as you're not doing something outrageous you'll probably be ok. Best thing I can do is list some of the common scenarios I've found that might catch you out:

• If you're using media that's subject to copyright you may need to prove you have rights to use it (we had to prove we had rights from opta for developing dugout FC)
• If you're using chat (particularly anonymous), you'll need a way for users to report people and block people.
• If you're developing an app for a client who has a registered organisation you need to make them register their own iTunes connect account with their iban, don't try to use your own.
• Your app needs to have a functional use and can't be purely informational.
• Your app needs to be useful in someway shape or form for anyone that could come across it, not just specific users (e.g. invitation only)
• If you're attempting to white label an app, iOS state there needs to be a functional difference and not just informational.

With the above being said it literally depends sometimes on who views it.

What can I do to help avoid headaches during the process?

• Put the app through the review process early for iOS, if you check the option for manual release you could just leave it there and keep developing.
• Get all of your metadata early. There are tools for generating all sized icons, take screenshots of the app in the biggest iPad and iphone, you'll need these to submit, iTunes connect can now auto resize to smaller devices.

Hey Julia, although this is more of a react than react native question I’ll see if I can help point you in the right direction. This definitely seems quite unusual and isn’t standard for react to see this.

To me it sounds like some form of leak, e.g registering event listeners that don’t get unassigned, or some recursive hell. Did you try compiling your app in production mode and running the output with a simple http-server? Also, have you tried running in chrome and inspecting memory and cpu usage?

No problem! :)

It's a bloody pain!

I think I've got a post somewhere in GitHub saying this is the biggest pain point at the moment with core React Native, and I posted that in 2017 github.com/facebook/react-native/i....

I just use a combination of the keyboard avoiding view and react-native-keyboard-aware-scroll-view, I've always been able to achieve what I want but it's always fiddly.

Low, less than 10% maybe, but I've worked on some weird projects. There's so many repos now on GitHub when comparing to 2015.

Here are the times I've had to delve into native modules.

1. Fixing bugs in existing libs (e.g. react-native-navigation)
2. Developing an app that integrates to a car HUD (Had the innards of a car on my desk for months)
3. Writing a bridge that integrated with a custom bit of hardware we produced base on particle.io/
4. Writing an iOS native keyboard extension (there wasn't a good project that existed, I guess it's not a common use-case)
5. Writing an android module that talked connected to a hotel router.