Value Unit is an umbrella term for several general concepts, like product, project, initiative, program, and portfolio, to name a few. Agile Tools allows you to use the terms you are familiar with and not force you to use the lingo of other companies, frameworks, or practices.
The added value in Agile Tools is that you can create OKRs for any Value Unit you have defined on the platform. You are not limited to creating goals on Teams and Organizational Units. If you are using a prevalent Scrum framework at work, you can now join good practices, as Scrum is very much goal-oriented. Setting goals on products you create goes remarkably well with OKRs.
Value Units are a new concept, a unique feature of Agile Tools. Every company has developed its unique process to deliver value to end-users. Some are using projects, and some have large initiatives that transition to programs or portfolios, consisting of many smaller projects. Yet other organizations have already shifted to a product-over-project mindset and are therefore building and thinking differently. They also want to use the concept of a product in their daily digital activities. With Agile Tools, they can.