If she's happy, then YANBU.
But do have a think about how she is going to cope in 2 short years when she goes to secondary.
At 10, ds was cycling to school on his own l (but not home as there was a right turn we weren't comfortable with). He started cycling to and from school shortly before his 11th birthday (beginning of P7, last year of primary).
He was walking to school on his own from age 8 (iirc), but went to our of school club afterwards. I did follow him secretly the first few times though! About a 10 minute brisk walk, with a lollipop man for the one significant crossing.
He got a semi Smart phone got his 10th birthday - a 2nd hand one from his aunt (with our approval). He was on PAYG, so initially only used it for calls & texts (so it was really for our benefit
). He got his first proper smartphone when he was 12.
He didn't go on to Facebook until he was nearly 12 (towards the end of S1) although we'd said he could when he went to secondary. Rule was that I set up his account and knew his password. He's now 16 so I no longer know it!
He's only recently gone on to a contract (only £7.50/month), so he's used to using wifi when available rather than using mobile data.
It's best to develop freedom incrementally: his first "solo" excursions were when he was 4, to the post box around the corner (across a wide, quiet, straight road and then round the corner: 5 minutes maximum except the first time when he inspected every single stone on the walls on the way there and back) while I watched anxiously from the window.
We built from there. A wee trip to the park on his own with a friend. A trip to the local shops. Being left for half an hour. Being left for an hour while we went to Homebase which he hated with a passion
But you need to do what you and your dd feel comfortable with.