Russian citizens can get a visa to Tanzania on the border by filling out the form and paying 50 USD.

It is possible.

Russian citizens need a visa to visit Tanzania, which can be obtained not only in the Embassy of Tanzania in Moscow, but also upon arrival at the airport of the country. The visa entitles you to stay in the country for 90 days. Consular fee - 50 USD in both cases.

To obtain a visa upon arrival, you must have a passport with a validity period of at least 6 months at the date of entry, an air ticket for return journey, or a third country, a certificate of financial solvency (at a rate of 5000 TZS (~ 3 USD) per person per day), and also a photo and an immigration card filled in English and a health questionnaire that are issued at border crossings.