alphaTab is described as 'cross platform music notation and guitar tablature rendering library. You can use alphaTab within your own website or application to load music sheets from files like Guitar Pro or use the built in markup named alphaTex' and is a music production app in the audio & music category. There are more than 50 alternatives to alphaTab, not only websites but also apps for a variety of platforms, including Windows, Mac, Linux, Android and iPad. The best alternative is MuseScore, which is both free and Open Source. Other great sites and apps similar to alphaTab are TuxGuitar, Guitar Pro, Avid Sibelius and Rosegarden.
Impro-Visor (short for “Improvisation Advisor”) is a music notation program designed to help jazz musicians compose and hear solos similar to ones that might be improvised. The objective is to improve understanding of solo construction and tune chord changes.
Songsterr is an archive of guitar, bass and drum tabs. It is collaboratively built and maintained by your fellow music lovers. Anyone with Internet access can contribute new tabs and make changes to existing ones.
Power Tab Editor is a free tablature authoring tool created by Brad Larsen for Windows. It is used to create guitar, bass and ukulele tablature scores, among many others. The current version uses the *.ptb file format.
Finale is proprietary scorewriting software developed by MakeMusic, Inc. It displays music primarily in music notation and allows for multiple tracks and very specific tweaking of instrument sounds for each track.