Hello
With Document5 i found the button and i could delete what i underline. Where is this file stored? can i drop this file to my computer with the annotations?
Withpdf reader i could find the annotains but i cannot delete them. How can i do that? where is the he file stored? with this app i've got advertisement some times. How can i avoid them?
What tool would you recommend for editing pdfs? is there any tool , as ibooks that allow me to modify the brightness. In some forums i read that the best tool is goodtoread what is your opinion?
For the Document tab of Documents 5, unless your file is within a Sync Folder (folder with a cloud on it) you set in the Network tab, it is always local to your device*.
If you can access iCloud Drive on your computer, you can tap and hold your file, and then drag it on to the iCloud tab. The file will then appear in your
Documents by Readdle folder within the iCloud Drive. If you don't want to use iCloud Drive, you may also
connect to third party services via the Network Tab, and selectively sync your folders, which the folders will appear under the Documents tab as mentioned. The annotations made by Documents 5 (or PDF Expert 5) are visible on your Mac or PC - well, at least iBooks on the iPad and Preview on my Mac can show the annotations without issues.
Adjusting brightness is possible with PDF Expert 5 on iPad, or Documents 5 that is installed alongside it. There is an "Aa" icon at the top center that will trigger a popover sheet, which provides options like day/sepia/night mode and scrolling directions. You may also try the Night Mode (if you are using iPhone) by tapping the top right most button.
P.S. If you need PDF editing, I recommend PDF Expert by Readdle (i.e. Documents 5 "add-on") as it has the cleanest, most elegant and smoothest UI among all the apps I've tried. GoodReader is a bit bloated and sluggish scrolling (especially the bouncing animation at the front page and the end), while PDF Reader 6 and Adobe Reader with the developer's own cloud sync service is not my cup of tea... Readdle's PDF Expert is a bit pricey anyway, but the support is real human backed

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* Documents 5 and PDF Expert 5 provide an iTunes File folder that allows you to move files in and out within the File Sharing section of your iTunes's App tab on the PC or Mac.