You will find a lot of comment on this matter by doing a simple search of url shortener seo on Google.
You will find that much of the information is a few years old and quote Matt Cutts who has been gone for years now. For this reason, I recommend caution. Any tactic that has existed for a period, would by now, be abused and targeted for scrutiny.
Here is a list from MOZ:
DoFollow links of this type work like any other link with a 301 redirect. There is no difference. However, I must caution that these URL shortner links can be spam none-the-less and are subject to the same criteria that any other link is subject to.
If you are intending to create a link campaign around URL shortner links, I would advise against it. Google still prefers organic links. Instead, I would advise seeking links within content as you would for any other link campaign. If some of these happen to be shortened URL links, then so be it. What is most important for a link is the context of the content surrounding the link, the link text, the relevancy of the link, etc. Seek these and do not target a specific link type, then you should be okay. However, do not over do it. Links should appear to be organic.