One list for the whole family
Parents create the list and add items with a price and a shop link. They share the link in the family group or in a message to each guest. Grandma in Krakow and the godfather in Gdansk see the same list and what is still free - with no phone calls to agree who buys what.
In the note for guests it's worth saying that a gift doesn't have to come from the list, or asking for a small keepsake instead of another watch.
Keepsakes and practical gifts
Both keepsakes and things a child will really use work well on the list: a bike, a watch, books, sports gear, a family day out. For an item needed in several pieces, guests can't reserve more than the number you enter.
Godparents chip in for a bigger gift
A pricier gift, like a tablet or a bike, is often bought by several people together. You turn on a group gift for that item. Guests join, the buyer closes the group and gives a bank account or BLIK phone number, and everyone sees their share. Payments go straight to the buyer, and yay.gift only helps confirm who has paid.
The child gets a surprise
Parents as organizers see which items are taken but not who bought them. Only the guest knows what they reserved, so the communion day still has its surprise.
How to put together a communion list
A good list has items at different prices: small gifts for the wider family, something mid-range for aunts and uncles, and one bigger group gift for godparents and grandparents. Give every item a price and a shop link, and in the note for guests mention the size or color if it matters. You can keep adding to the list until the day of the ceremony.