Unless you download Windows 10 apps from the Microsoft Store, most installed software still won't auto-update. Web browsers will notify you of a new update, your security software will auto-update and so will Windows itself, but most other tools sit happily on your system and you might never know when a key update is available unless you go checking.
IObit Software Updater is a free tool which will scan your system, check for all your installed software, compare this to an online database and then will warn you if an update is available.
That's the good news. The less good news is that the database is very small and finds only essential software updates. Worse, one of the recommended updates was for Google Chrome, which auto-updates anyhow. The other was for Avira Safe Shopping, which although must have been embedded in the Registry, wasn't installed on our system.
We then ran a comparison to our own Updater Tool, which listed updates for Adobe Brackets, Xara Photo & Graphic Designer and Amazon Music, tools which didn't appear in the IObit Software Updater, at all.
IObit Software Updater also offers a number of recommended tools you can download from various categories, some we'd recommend, others we perhaps wouldn't.
The Software Updater will create a system restore point, in case you update software which causes your system to become unstable. You can also schedule automatic updates and add programs to your 'ignore list' (it offered to add Avira Safe Shopping to our ignore list, for example).