Get Expensify (free for a single user from App World). I have been using it for the past three months and have found it to be great. The interface is very simple. I tried ProOnGo also, but found Expensify to be better suited to my needs. The app allows you to add expenses and receipts; all reports etc. Must be generated through a web portal (which I prefer). Expensify does not store information on the device (it uploads it directly to their platform) so you need cell coverage for it to work. When I don't have coverage, I just keep the receipt and enter it later. It only takes two clicks of the scroll button to enter a new expenses (unlike ProOnGo which I found required a few more steps).
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True Ascendo Money is very good, but cost a huge 29.99$.
for free try toshl. download it from Mobile Expense Tracker - Toshl, it has some bugs like will not sinc over the internet. but handy if you keep low and track your expenses.
I travel for business extensively and have found Expense Manager to be great. Stores data on device and send report spreadsheet to your email address. Multi currency etc.
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