After returning to Russia from Leipzig, Langer began teaching. In 1860, he was invited by
Nikolai Rubinstein to teach piano and
music theory at the Russian Musical Society in Moscow. Six years later, he became a professor of piano at the Moscow Conservatory. His most notable students include the renowned virtuoso teacher
Karl Kipp, composer
Sergei Taneyev, cellist
Anatoliy Brandukov, and
Antonina Miliukova, who later married Tchaikovsky. Langer transcribed the
orchestral and
symphonic works of Russian composers including
Mikhail Glinka,
Alexander Dargomyzhsky,
Anton Arensky, and Nikolai Rubinstein for piano in two, four, and eight hands. His most notable transcriptions are those of Tchaikovsky, his friend and colleague at the conservatory who dedicated his
Capriccioso (op. 19 no. 5) to Langer in 1873. Two letters sent from Tchaikovsky survive, one from April 1880 in
Saint Petersburg and another from September 1880 in
Kamenka, Russia. In the latter, Tchaikovsky asks for his aid in republishing 4-hand arrangements of
Symphony No. 1,
Symphony No. 3, and
The Tempest. He died on May 7, 1905, in Moscow, aged 70. == Personal life ==