for real, they are all garbage

NOT: if (matched.length > 5 && event.target.value !== ""){ matched = matched.slice(0,5); }else if(event.target.value === ""){ matched = [] } BUT: if (event.target.value === ""){ matched = [] }else if(matched.length > 5){ matched = matched.slice(0,5); } EVEN CLEANER: event.target.value === "" ? matched = [] : matched.slice(0,5); Since the slice method uses the lenght of the array when the index is greater, you don't really need to check if the length is greater. You first check your lenght and then you make sure it's not empty, if there aren't more then 5 results or the string is empty, you check again now to make sure it is empty. I just check if it's empty, I don't need to check anymore if it's not empty, cause by the time the code get's executed I already now it isn't Your options also could be rewritten: let options = ctx.interval === '1D' ? OPTION_HOUR_MINUTE : ctx.interval === '1W' || '1M' ? OPTION_MONTH_DAY : OPTION_MONTH_YEAR; And how about your names? They should be descriptive yes, but also easy , when everthing starts with selected- or searchedCurrency, that's everything but, the same for giving the same names and just placing underscores after them Finally you always refer to the finish product to explain, it would be better if you show what you're developping, your missing imports and exports I already notice, yet it takes you more then half an hour in the video to notice. I'm a java developer, so I kind of know what I'm doing, but someone who has no experience get's stuck and dosn't know what to do. Same for packages, you just start, expecting us to know what packages to install. I haven't seen you install router-dom for example? Axios, yes later on, cause you forgot youself, I had it already installed ;p If you show in the video what you're developping, you would have noticed the issues sooner

Yes of course 🙂

If you dont want it turns back to default language you could store the selected language using Asyncstorage

It will be same