What are some alternatives?
When comparing FileApp and i-FunBox, you can also consider the following products
Documents by Readdle - A central hub for all your files.
iMazing - iMazing lets you transfer music, files, messages, apps and more from any iPhone, iPad, or iPod to a computer, Mac or PC. Manage and backup your iOS device simply without iTunes. (was DiskAid)
iFile - If you need a new file manager for your device, iFile might be the answer you seek.
iExplorer - iExplorer lets you easily transfer music, playlists, text messages, files and more from any iPhone, iPod, or iPad to a Mac or Windows computer and iTunes.
GoodReader - With GoodReader on your iPhone, iPod Touch or iPad, you can read virtually anything, anywhere.
PhoneView - With PhoneView, you can view, save and print all of your iPhone and iPad messages, WhatsApp messages, voicemail and other data directly on your Mac. Save your SMS, iMessages and WhatsApp messages.