Crimean Tatar is written in both Latin and Cyrillic. Historically, the Arabic script was also used.
Since 1990s when Verkhovna Rada of Crimea officially accepted the new Common Turkic-based Latin alphabet it had been dominant mostly on the internet while the Soviet Cyrillic alphabet remained dominant in printed productions. After 2014 Russian annexation of Crimea Russian government requires the use of Cyrillic script only. In 2021 Ukrainian government started the switch of Crimean Tatar language to the Latin script.
History
Arabic script
Crimean Tatars used the Arabic script from the 16th century to 1928, when it was replaced by the Latin alphabet based on Yañalif. The Crimean variant contained a couple of modified Arabic letters.
1 — The letter ﻙ (kef) was often used in place of ﮒ and ﯓ.
Latin alphabet
In 1928, during latinisation in the Soviet Union, the Crimean Tatar Arabic alphabet was replaced by the Latin alphabet based on the Yañalif script. This alphabet contained a number of differences from the modern variant. Particularly, the letters Ь ь, Ƣ ƣ, Ꞑ ꞑ, Ɵ ɵ, X x, Ƶ ƶ, I i instead of the modern  â, Ğ ğ, I ı, İ i, Ñ ñ, Ö ö, and Ü ü.
Modern alphabets
Cyrillic
Cyrillic for Crimean Tatar was introduced in 1938 as part of Cyrillization of languages in Soviet Union. It is based on Russian alphabet with no special letters. From 1938 to 1990s, that was the only alphabet used for Crimean Tatar.
*Гъ (ğ), къ (q), нъ (ñ) and дж (c) are separate letters of the alphabet (digraphs).
Latin
Modern Latin alphabet for Crimean Tatar was introduced in 1990s. It is based on Turkish alphabet with three special letters — Q, Ñ, Â. Its official use in Crimea was accepted in 1997 by Crimean Parliament. In 2021 it was approved by the government of Ukraine, to be adopted in education by September 2025.
*Ââ is not recognized as separate letter. It is used to show softness of a consonant followed by Aa.
Cyrillic to Latin transliteration
Sample of the scripts
Article 1 of the Universal Declaration of Human Rights:
References
Кай И.С. Руководство для обучения крымско-татарскому языку по новому алфавиту — Симферополь, 1928. Alem-i-Medeniye