Most anglers buy a tackle bag the same way: the starter box is full, the lid will not close over the worms, and there are now three loose utility trays rattling around the truck. A soft tackle bag fixes that by carrying those trays upright in one place, with pockets for pliers, spools and a bag of plastics. This page is only about that shape: a bag with a shoulder strap and handles that sits on a dock or a boat deck. If you want the trays on your back, the backpacks and slings have their own guide, and hard boxes and stocked starter kits live on the beginner tackle box page.
The decision that matters most is tray size, and it is easy to get wrong. A 3600 utility tray is the smaller one, roughly 11 by 7 inches. A 3700 is the bigger one, roughly 14 by 9 inches, and it is a common choice for sorting crankbaits, jigs and soft plastics. A bag built for 3600s will not take a 3700 at all, so count the trays you already own before you look at anything else. Second, check whether trays come in the box. A bag-only listing is not the full cost if you still need to buy trays.
After that it is capacity and the base. A bag that holds 12 trays is great on a boat and miserable to carry a quarter mile down a bank. A molded or PVC-coated bottom keeps a wet deck from soaking through. Tom has not handled or tested these bags. They are ranked from published specs and the ratings Amazon buyers left, and each listing's tray size and capacity below comes from that listing's own description. Check the current price on Amazon before you buy.