iMyFone iTransor for WhatsApp - iMyfone iTransor for Whatsapp is the best transfer tool which can help you transfer Whatsapp cross-device.
Titanium Backup - Titanium Backup is a very old backup app that has been around since the early days of Android. In fact, it's one of the few apps that covers all versions from 1. Read more about Titanium Backup.
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)
oandbackup - Make backups of selected apps on your device and restore from those backups.
CopyTrans - CopyTrans is a tool for managing the files on your iPhone or iPad through your computer's interface.
MIUI Backup - built in backup manager in xiaomi devices