I'm a real estate agent and spend most of my day

Hi all. I'm a real estate agent and spend most of my day in the car or at showings. Clients constantly send me photos of documents through messengers, and I need to turn them into PDFs for the agency or merge them into one file right away. Doing this later at the office means delays. I'm not at a desk most of the day, so whatever it is needs to work on a phone with a so-so connection. Most of the documents are passports, contracts and utility bills, so privacy matters too. Anything that works well on an iPhone without installing yet another app?

Same life here, half my paperwork happens in the car between showings. I use Convert2PDF, an online PDF converter that works fine in Safari on my iPhone. Client photos go through JPG to PDF or Images to PDF, and when I need to combine a few documents, Merge PDF handles it. No app, no account. Files are processed on the phone itself, not uploaded, which is reassuring with passport scans. On a phone I'd keep the batches small though, ten or fifteen photos at a time, otherwise it gets slow. It saved me a few trips back to the office every week, which is a real time saver in this job. Then I just send the result straight to the agency from the same phone.