AllShots
The moment you ask a guest to install something, you lose a third of them. Here is how photo collection works when the only requirement is a phone with a camera and a browser.

At a wedding or a company party you have one shot at getting people to participate, and it happens while they are holding a drink. An App Store page with a login screen behind it is where participation goes to die. A web page that opens the camera is not.
AllShots is built around that: the guest side is a website. The iPhone app exists for hosts and for guests who want it — it is never required.
iPhone. Scanning the QR opens a small page with two buttons: Continue in browser and Get the app. Continue in browser opens the web camera in Safari. No account, no download.
Android. The QR goes straight to the web camera. There is no Android app, and none is needed.
Laptop or tablet. The link opens the gallery and an upload button — useful for the photographer’s assistant or a guest who took photos on a real camera.
A throwaway session is created behind the scenes so the guest’s shots count against their own allowance and their photos stay attributed to them. That session lives on their phone; there is nothing to remember.
All of it: how many shots each guest gets, whether the album is shared or private, whether photos show instantly or the next day, and every photo in the gallery, which you can hide or delete. Guests can report a photo; you decide.
Create an event, scan your own QR with a second phone, and watch the photo land in the gallery. It takes two minutes.
No. No account, no email, no download. They scan the code and the camera opens in their browser.
Safari on iPhone, Chrome on Android, and any modern desktop browser. If the phone can open a web page and use its camera, it works.
In a shared album, yes — that is the default and most of the fun. Switch the event to private and each guest sees only their own uploads.
No, and guests do not need one: on Android the QR code opens the web camera directly. Hosts manage everything from the browser at host.allshots.app.