This is unofficial Path of Exile Skill Tree app.
It allows you to create builds for any Path of Exile character and share them with a build link.
It include full jewel support for jewels with radius this include modifying tree in radius according to jewel rules.
You can enter your gear totals for life mana and energy shield and see exact values for Max Totals Regen and Leech Cap.
You can specify your weapon and main skill type and see combined totals for all relevant stat increases like damage crit attack or cast speed etc
You can select your main skill gems and see your total cost to cast csts per second and how much seconds you can sustain this.