My phone and tablet is not working with the software.
Hi there axess-arborist,
Being able to use the mobile app for on-the-go work is an asset that many users love when it comes to QuickBooks Online, and I'm excited that you'd like to use it as well. Even if you're using a mobile browser instead, it's a useful option to have to make sure you can continue to access your books away from a computer. I'd be happy to help you get back on track with this to make sure that you can start entering your transactions from your device.
As Fiat Lux hints at, there are system requirements for QuickBooks Online, even with it being a cloud software. The QuickBooks Online access for mobile devices article has some specs to keep in mind for when you're looking to use the mobile browser for QuickBooks Online, but these could also be useful for considering the mobile app as well. If it's the app you're having trouble with, I recommend uninstalling and reinstalling it on both devices to see if that helps the issue you're running into.
If these don't do the trick, please elaborate on what you mean and what's happening when you say your devices aren't working with QuickBooks Online. The more detail, such as error messages you're seeing or describing the behaviour of the program, will help with tackling the problem. The QuickBooks Community is a public forum, so keep that in mind if you do decide to share more information here so that you can protect your personal details.