On Android you'll have to go to the Playstore & download Tapatalk..
me thinks it's paid, not sure if there is a free version too..
Download & install, open the app, search for 'nikonites' & provide login details.
About the other part, are you asking how to remove an app?
Goto settings>apps.
look for the app you wish to remove, click on it & you'll get some option like clear defaults, clear cache etc.
One of the options is to 'uninstall' which will remove the app.
Easier option would be to download any uninstaller app from the palystore & use that to remove programs you don't need.
i use 'easy uninstaller'