To use a different way of capturing dates in PowerApps:
Frankly, the default date picker is clunky and you have to constantly navigate between the arrows to select dates. Can become quite a nightmare for end users.
The better alternate is to just drop a text input into the PowerApps Canvas. You can format it when referencing to a date format you prefer using the function
When you collect it to a collection, or patch or update it to a data source. Just reference the DateValue function. It should mimic it as the Date control does in PowerApps.