Full Screen recommended. Connect every "Island" (represented by circles), into a SINGLE interconnected group. To do this, draw "Bridges" between Islands. The number in each circle (1-8) states how many Bridges must connect to that Island. Bridges cannot cross each other, can only be drawn horizontally or vertically, and there can be a maximum of two Bridges between any pair of Islands. To draw a Bridge between two circles, click on the edge of a circle on the side that you want to create or modify a Bridge. Repeated clicks cycle through the number (0, 1, 2, 0...) of possible Bridges. Scroll down for some tips. A "1" cannot connect to another "1". That would make it an isolated Island (not allowed). A "2" cannot be connected to another "2" by two Bridges. Same reason as above. A "3" that can only be connected to two other Islands, must have at least one Bridge to each one. From any Island, surrounding Islands that have already had their Bridge counts satisfied, can be ignored as possible Bridge destinations. Good luck!
Thanks to @grandpasp for the original puzzle! I couldn't solve it on my own, so I thought it would help if the islands turned green once they reached the required number of bridges.