There’s currently a dropdown of sub-categories when selecting a category eg. Electronics & Gadgets, which I feel is more useful than going to a next screen with only the sub-categories. It would be rather tedious to keep returning to the main screen of categories if you do not manage to find a suitable sub-category after tapping in.
Also the proposal to change the ‘promote’ icon to a ‘share’ icon is currently in place in Carousell for Android.
In fact the current ‘promote’ icon does look similar to the ‘share’ icon for iOS. So I’m not sure if it helps to change the icon to one that Android users are more familiar with.