Dd is now 12 but started going into town with her friends in Yr 6 (I was trying to get her a bit more independent before starting secondary school).
They mainly go to mcdonalds or starbucks, flying tiger and primark.
We got her a bank card as so many shops wouldn't take cash due to covid. We've found that dd is very sensible with her money, so I tend to top up her bank card with £30 when it gets low (I want her to have enough in there to cover most emergencies).
Sometimes the £30 will last for 2 months, but during the school holidays she can arrange to go way more frequently, thus needing top ups more frequently. And I want to encourage her meeting up with friends and wouldn't want her missing out because she's got no money.
It depends on what type of spender your dc is I guess. If they are likely to spend all the money in one go on every trip then set weekly pocket money. If they're sensible and don't blow it all then just top up when needed.
Dd is now almost at the stage where going clothes shopping with me is an utter trial for both of us, so I'm thinking of giving her a clothing budget and she can buy what she wants rather than my sensible hunt for 100% cotton tshirts. Plus she's started buying her own skin care and face masks, so that's something I'll divert from the weekly food shop budget to her.
Every trip she takes into town, she always brings back a little gidt for her younger brother. Usually a 50p pack of popping candy or a lollipop, or a car from the pounds hop. Something cheap, but it always makes his day. And I'd hate to limit her money in a way with a set amount of pocket money in case she felt like she couldn't do this anymore