Guitar Pro is a much-loved guitar tablature (chords, six line-spectrum, BASS four-line stave) drawing, viewing, printing, listening and learning software by guitarists (from France). At the same time, it is also an excellent MIDI sequencer and MIDI production helper tool, which can output the standard format of MIDI.
Transposer is a very, very old (written in 1998, AppNee never cares about this kind of thing, as long as it can still solve users' problems) but handy and user-friendly tiny app (< 1 MB) specially designed to transpose a chord file with different keys.
Beginning Fingerstyle Blues Guitar is a classic and excellent tutorial book (published in 1993) for playing the acoustic blues guitar. It broke down the whole learning process of fingerstyle blues step by step in only 98 pages and was written especially for beginners.
MagicScore is a classic, wonderful and lightweight music score editing and composition software, provides a wealth of options specially for students and teachers in the music college, as well as many amateur music lovers. For both people who are interested in music creation and professionals specifically involved in music, they all can use it to complete their music creation.
A Modern Method for Guitar is a very classic series of teaching materials for professional and systematical learning of guitar play and creation, written by Berklee College of Music. You know, there have been a lot of guitar masters start to use this set of textbooks since 40s in the last century, because it covers a extremely wide of content, and has very strong practicability.