I am from Iran and I am going to study in Germany in a few months. My boyfriend (Iranian) is also going to start his studies in U.K. I am wondering if it is possible for both of us (or even one of us) to apply for a visitor visa so we can see each other during this time. I really would appreciate any information.
A long-term UK Visit visa of 2, 5 or 10 years is available but approval typically requires a strong travel history eg several previous visas for the UK or similar eg Canada, US, Schengen. The UK Standard Visit visa is valid for up to 6 months and is usually multiple entry. https://www.gov.uk/standard-visitor-visa so you should be able to use it for eg weekend visits from time to time. Your study visa for Germany should count in your favour.