[alexjj]

There's no "nice" app where you click on drop downs or type in amounts and then it appends it to your ledger file.

Generally, and it's been discussed a lot on the mailing list/irc, people end up finding just writing down transactions in a text file works best. e.g. google keep, or simplenote, or Notes app etc.

I keep my ledger file on dropbox, so I can edit it directly.

I've not tried hledger-web on my phone to see what it looks like, but that has an add transaction function. So you could just go to your site and edit it. Obviously want some security to prevent others accessing it, e.g. VPN to home network.