The fastest way to start finding things in the night sky costs nothing and is already in your pocket. Hold your phone up, and a decent stargazing app will name the bright dot you’ve been squinting at: Arcturus, or Jupiter, or the International Space Station about to clear your roofline. No telescope, no printed atlas, no memorising constellations first. That’s the pitch, and it mostly holds up.
The catch is that the app store is stuffed with near-identical star maps, half of them want a subscription, and the headline “just point your phone at the sky” feature breaks in ways nobody warns you about. Here’s how I’d pick one, based on what I actually keep on my phone in Nicosia and hand to friends who’ve never found anything but the Moon.
What a planetarium app actually does
Every app in this guide is a pocket planetarium. It knows your location (from GPS), the exact time (from the phone clock), and where the planets, stars, and a few thousand deep-sky objects sit relative to you at that moment. From those three inputs it draws the sky. It’s the same calculation a desktop planetarium has done for decades, now recomputed on your handset several times a second.
Two things follow from that. First, the app doesn’t need a signal or a data connection once the star catalogue is downloaded; the maths is all local, which matters when you drive somewhere dark and lose reception. Second, the app is only as honest as its inputs. Feed it a confused compass reading and it will point you confidently at the wrong star, with no idea it’s lying. More on that below, because it’s the single biggest source of “the app is broken” complaints from beginners.
Start here: the free ones worth using
If you want one recommendation and no decisions: install Sky Tonight (Vito Technology, iOS and Android). It’s free, and as of mid-2026 all the actual sky data (every planet, constellation, and event) works without paying. Premium only removes ads and a few interface limits. It has a clean point-and-identify mode, an augmented-reality overlay that puts labels on your camera view, and a “stargazing index” that scores tonight against Moon phase, cloud cover, and light pollution. For a first-timer standing in a car park wondering what that orange star is, it’s the shortest path to an answer.
The other name you’ll hear everywhere is Stellarium, and it’s worth being precise about the versions because they’re easy to confuse:
- The desktop program (stellarium.org) is free, open-source, and the reference standard. If you have a laptop, install it; it’s what I use to plan a session before I leave the flat, and there’s a browser version at stellarium-web.org if you don’t want to download anything.
- Stellarium Mobile on Android has a free tier: open-source, no ads, but it caps the star display around magnitude 8. That’s more stars than you’ll ever see naked-eye from a city, so the limit rarely bites a beginner.
- On iOS, the free mobile version is gone. The App Store now only lists the paid Stellarium Mobile Plus (about $13.99 at the time of writing). iPhone users who don’t want to pay can just use Stellarium Web in Safari, with the same engine at no cost.
Between Sky Tonight and Stellarium you’re covered for free on any phone. Everything below is optional.
When it’s worth paying
Paid apps buy you two things: bigger catalogues and telescope control. Neither matters on night one. Both matter later.
SkySafari (Simulation Curriculum) is the app serious observers graduate to. It ships as three separate apps — Basic, Plus, and Pro — at roughly $4.99, $12.99, and $19.99 respectively as of mid-2026, and they go on sale often enough that it’s worth waiting for one. The difference is catalogue depth: Basic knows around 120,000 stars, Pro pushes past 100 million plus millions of galaxies. Plus is the sweet spot for most people, and both Plus and Pro can drive a GoTo mount over Wi-Fi or Bluetooth, which is the real reason to own it. If your observing is still naked-eye or binoculars, you don’t need this yet. Buy it the week you get a tracking mount, not before.
Star Walk 2, also from Vito Technology, deserves a note mostly because its naming has drifted and confuses people. What used to be “Star Walk 2 Free” is now sold as “Star Walk 2 Plus”: free to install but ad-supported, with a one-time purchase or subscription to strip the ads and add its deep-sky content. It’s polished and beginner-friendly, but given the same company’s Sky Tonight gives you more for free, I’d start there and treat Star Walk 2 as a matter of taste.
A rule of thumb I’ll stand behind: no app is worth a recurring subscription until you’re using it to point hardware. For finding things with your eyes, the free tier of Sky Tonight or Stellarium is all you need.
How “point your phone at the sky” really works, and why it lies to you
This is the feature that sells these apps, and the one that most often makes a beginner think the app is broken. It isn’t broken; the app is doing something hard with cheap sensors, and the sensors are the weak link.
To draw the right patch of sky in real time, the app has to know two things about how you’re holding the phone: which compass direction it faces (azimuth) and how far up it’s tilted (altitude). Altitude comes from the accelerometer and gyroscope, and those are reliable, because gravity is a steady reference. Azimuth comes from the magnetometer, the phone’s tiny compass, and that’s where it falls apart.
A magnetometer measures the Earth’s magnetic field, which is weak. Anything ferrous or magnetic nearby overwhelms it: a car body, a metal railing, rebar in a concrete balcony, the speaker in the phone itself, and especially the magnets in a MagSafe or flip-cover case. When the reading is corrupted, the app swings the whole sky sideways by 20, 40, sometimes 90 degrees, and points at Vega while you’re looking at Arcturus. It has no way to know it’s wrong.
Two habits fix nearly all of it. Calibrate the compass by waving the phone in a slow figure-eight a few times when the app or the OS asks, which re-teaches it the local field. And step away from cars, railings, and reinforced walls before you trust the pointer. From my balcony the reading is hopeless within arm’s reach of the aluminium railing and fine two steps back. If the labels still feel offset, cross-check against something you already know: line the pointer up on a planet you’ve identified, and if it’s off there, it’s off everywhere.
Turn on red mode before you go out
Every app on this list has a night mode that tints the screen deep red. Turn it on, and not for aesthetics. Your eyes take about 20 to 30 minutes to reach full dark adaptation, and a single glance at a white phone screen resets a good chunk of it in a second. The rods that pick up faint stars are wiped out by bright light and recover slowly. Red light, at low brightness, leaves that adaptation mostly intact. I go into the reasoning in why your eyes need 30 minutes to see real stars, but the short version is: white screen at full brightness is the fastest way to ruin your own night. Set the app to red mode and drop the brightness to its floor before you’re out under the stars.
Plan indoors, identify in the field
The mistake I made early on was treating the app as a field tool only. It’s better as both. Before you leave, use the desktop or web version to answer the boring questions: is anything worth seeing up tonight, when does it clear the horizon, is the Moon going to wash it out? Ten minutes with Stellarium at the kitchen table turns a vague “let’s look at some stars” into “Saturn’s up by 22:30 in the southeast, and the Summer Triangle is overhead all night.”
Then, outside, the app switches roles. It becomes the thing that confirms the shape you’re half-seeing. Point it at the three bright stars high overhead and it’ll tell you you’ve found the Summer Triangle; sweep it along the ecliptic and it’ll sort out which planets are naked-eye tonight. The workflow that sticks for beginners is: learn one anchor pattern with the app’s help, then use that anchor to star-hop to fainter things without the phone. Five star-hops from the Big Dipper is exactly this kind of practice: the app gets you to the Dipper, your eyes do the rest.
The thing every app guide leaves out
An app is a crutch, and that’s fine — crutches are useful. But lean on it too hard and you never actually learn the sky; you learn to hold up a screen. The observers I know who can name things instantly all went through a phase of deliberately putting the phone away after it pointed them to a starting star.
And the phone has a failure mode a printed chart doesn’t: it dies. Cold nights drain batteries fast, and there’s a particular kind of frustration in reaching a dark site with a flat phone and no idea what you’re looking at. A £10 planisphere — a rotating paper star wheel — weighs nothing, needs no charge, and shows the whole visible sky for any date and hour. Keep one in the car with a red headlamp. It won’t identify a random satellite for you, but it’ll always tell you where the constellations are, which is most of the battle.
Start with Sky Tonight or Stellarium tonight, learn one pattern, then look up without the screen. The apps are the best on-ramp beginners have ever had. Use them to get started, then grow past them.