In my current project the webApp has a lot of functions the user can interact with. Most of them are actions to manipulate data in database, main data, address, favorites, shopping cart, update order, read message, etc..
For almost all of these actions I'm providing the user with a small toaster and a brief message about the result of the action. For example:
Toaster shows up in the bottom-center of screen - On mobile, it has a 90% width;
- The user can have a maximum of 3 addresses (and starts with none);
- User add an address -> Success notification -> 'New address added';
- User set the address as default -> Info notification -> 'Address set as default';
- User delet an address -> Success notification -> 'Address deleted';
- User has already 3 address -> I hide the form and show a message "You already have the maximum number of addresses."
It's just for the address part, there is still other areas such as the personal information, etc..
I'm feeling it's a little too much of notifications, but in the other hand, all of these actions are important to the workflow of the webApp, because the user needs to have at least one (and default) address, but he can choose from the 3 he has when he's in the checkout proccess, for example.
So my question is:
When should i use/consider using a notification based on an user's action?
Should it be used when he insert/update a data? When it's a critical data?
What criteria should i have in mind to improve the user experience, give him just enough feedback of what he's doing but in the same time don't let anything important behind?