Most marketing advice is written for companies with a marketing team and a budget to match. Follow it as a two-person dev team and you'll pour weeks into things that make no difference, while the four that matter sit undone. So here's the short list, and what you can happily ignore.
What you need
A page for people to land on. One page that says what you make, who it's for, and why it's worth their time, with a clear next step. Not a twelve-page site with an "our values" page nobody reads. One page that turns a visitor into a sign-up or an install.
A way to keep the people who show up. Most first-timers won't buy on the spot. Get their email so you can reach them again directly, instead of praying a feed shows them your next post. Email is the one channel you own, and for a small team it's the one worth building first.
A reason to be found. People are already searching for what you make, or for the problem it solves. A few useful pages and posts, written around those searches, bring a steady trickle of the right people, and you don't pay per click for the privilege.
A launch that lasts longer than a day. A launch works as a run-up and a follow-through. One big push on the day, then silence, is how good products sink without trace. More on that another time.
Do those four well and you're already ahead of most teams your size.
What can wait
Being on every platform. Pick one you can keep up with. Five half-dead accounts look worse than one that's alive.
Paid ads before your message works. Ads just spend money faster on whatever you already have. If the message isn't landing, you're paying to learn that. Sort the message first.
Chasing follower counts. Followers and impressions feel lovely and mean little. Sign-ups, installs and sales are the numbers that pay rent.
Elaborate automated sequences. One good welcome email beats a ten-step monster you abandon in the builder. Start small.
A posting schedule you can't keep. One useful post a month you publish beats three a week that quietly stops in February.
Small teams win by doing a few things properly and sticking with them. Work out which handful matter, build those, and leave the rest until there's a reason to care.
If you're a small team working out where to put limited marketing time, that's what I help with. See how I work with games and apps, or what I do as a freelance marketing consultant.