bought the 830 last week and was surprised not to find the lumia camera app as default but after reading several forums it was clear the 830 does not have the options for the camera as promised (actually very disappointed in Microsoft because of this) the denim firmware installed is clearly not the latest denim but I did find a way to go around it by reading many posts this is the one that made lumia camera (after downloading it from the store) work:
"When the app opens and the message appears, press and hold the back button. It will open multitasking. Now just go back to Lumia Camera and it's done.
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Hi.
I was unable to see the Lumia Camera app on the store, but today I found it and installed it and the same annoying message appeared to me. I found a solution: When the app opens and the message appears, press and hold the back button. It will open multitasking. Now just go back to Lumia Camera and it's done. I have a Brazilian Lumia 830 with Canadian firmware. I'm very disappointed with Microsoft, because they lied about the Lumia 830 and Lumia Denim update...
The app is working very well and WOW, it's very fast, but no rich capture yet, at least not for 830.
Thank you for the tip Pedro!!!! This also worked for me!!! Hope it will last and not brake again....But still MSFT needs to iron out these issues. We are talking about a device (830) that is very new in the market and should not have these issues.
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thanks to RafinhaPedro for posting this solution/work around!!!
lumia 830 rich capture - Microsoft Community