Back in the day, tables were the only option. Today, most recreational divers wear a personal dive computer and for good reason.
Your computer calculates your depth, bottom time, ascent rate, and no-deco limits in the moment. Tables give you a static plan. When you change depth partway through, it updates. A table can't.
Wrist computers are what the majority of divers use now. They're compact, easy to read, and you'll use them as a watch between dives. Console-mount computers are still around but less people choose them now.
Entry-level computers run about a few hundred dollars and handle everything most divers needs. They give you depth tracking, bottom time, NDL, a logbook, and sometimes an entry-level apnea mode. Mid-range includes transmitter compatibility, better readability, and additional mix options.
Something new divers overlook is algorithm differences. Some models are more cautious than others. A conservative algorithm means further reading shorter bottom time. Liberal settings allow longer bottom time but at a thinner buffer. Both work. It comes down to what you're comfortable with and experience level.
Worth talking to people at a Cairns dive shop who's used a few different brands first. They'll have honest opinions on what's good and what isn't just marketing. The better Cairns dive stores have product guides and honest reviews on their websites as well