All the above is great advice and its true there is a wealth of apps, tools, and services out there that can help you.
While you get up to speed on what is available I’d suggest you take some time to figure out what problems you want to solve with technology. At the end of the day they are all tools and you want to get the best one for the job. Also, in my experience adding tools successfully usually requires understanding your current processes and figuring out how they can be made better. Automating processes that you aren’t happy with just gives you processes you aren’t happy with just that they run faster/cost less/etc. .
Where are you major cost drivers in your business and what drives them? If any are driven by inefficiencies, communication, etc. you can look at tools for that.
Where do you spend the money on people expenses not directly related to generating revenue or building product? Can you find tools that help automate that work? Note: This doesn’t necessarily mean you make people redundant but you may find you can do more volume and not add non-sales and/or product resources as you grow.
Where do your sales people spend their time? Of those activities what are not related to actual selling and closing deals? Can any of that be eliminated or automated?
You can ask a lot of questions about your business and find opportunities to either automate, eliminate, or control costs with online tools or better yet just stop doing things that don’t contribute to sales, customer success, making your team better, or building product.