FaChords Guitar Rhythmic Trainer is an online tool that will help you develop speed and accuracy on guitar. It's well known that if you want to play fast on the guitar, first of all you must be able to play slow clear and comfortably. Then you can try to play a bit faster. Sometimes it's also useful to play outside of your comfort zone.
There is no shortcut; this is the only way to get fast picking speed. A useful available feature is the possibility to increase gradually and automatically the speed of the beat during the exercise.
For example, suppose you want to practice a musical sequence that you can play comfortably at 120 bpm. You set the initial speed at 120 bpm (or a bit less), the duration of the exercise, for example 20 bars, and the target speed, suppose at 140 bpm. Then you press the START button and begin to exercise. The Speed Trainer forces you to accelerate, but in a smooth and imperceptible way. The final outcome is that your fingers learn to play a bit faster little by little.
Several kinds of time signatures are available: 4/4, 3/4, 5/4, 7/9, 9/8, and more.