Search this question and you get lists of twenty-five apps, all described in the same enthusiastic language, most written by people who installed none of them. This page does something less satisfying and more useful: it tells you what separates a booster that does something from one that only appears to, so you can judge any of them yourself.

Disclosure, up front. We publish GameZapper, an Android booster. That is a conflict of interest, so you are not getting a ranked list from us with our own app at the top. You are getting the criteria, including the ones our app does not win on.

First, decide whether you need one

A booster's main real mechanism is closing background apps to return memory to your game. How much that is worth depends almost entirely on your phone.

On a device with 4 GB of RAM or less, it is a genuine and repeatable improvement: fewer reloads, less stutter at load points. On a phone with 8 GB or more, Android is already managing memory competently and you will often measure no difference at all. That is not a flaw in any particular app, it is what the platform allows. There is more detail in how much RAM you need for gaming.

If your problem is heat or the network, no booster of any kind will help, and you should start with the five causes of lag instead of the Play Store.

The options, compared

These are the apps and approaches that come up repeatedly in this category. The column that matters most is the last one, because every entry here has a limitation and the lists that omit them are not doing you a favour.

Option	Approach	Worth knowing
Your phone's built-in game mode	System-level: CPU and GPU governors, notification blocking	The only option that can touch clock behaviour. Free, already installed.
Game Booster 4x Faster	Closes background apps, clears memory	The "4x" is branding, not a measurement. Heavily ad-supported.
Game Booster (BGNmobi)	Launcher: add games, start them through the app	Straightforward and honest about being a launcher. You must launch from it.
GearUp Booster	Network routing, marketed at latency	Subscription. Route optimisation can help on poor routes and cannot beat physics.
GFX Tool and similar	Edits per-game graphics configuration	Modifies game files. A genuine ban risk in BGMI and Free Fire.
Google Play Games	Manages background work for integrated titles	Only affects games that integrate with it. No control elsewhere.
GameZapper (ours)	Closes background apps, DNS routing, live FPS / ping / temp / memory	We publish it. It cannot cool your phone or lower in-match ping either.

Those are Play Store searches rather than direct links, deliberately. This category is full of clones with near-identical names and icons, and sending you to a lookalike would be worse than costing you one extra tap. Check the developer name before installing anything here.

Which one, for which problem

If your phone has 4 GB of RAM or less

Something that closes background apps will help, and most of the apps above do that. The differentiator is not the boosting, it is whether the app is honest about the result and how much advertising you tolerate to get it.

If your problem is latency

A network-focused tool is the only category with a plausible mechanism, and even then it can only improve routing, not distance or congestion. Treat any specific percentage in the marketing as invented. Read what ping actually is before paying a subscription for this.

If your problem is heat

No app in the table helps, including ours. Lower your frame rate cap, take the case off, and see why your phone gets hot while gaming.

If you want to know which problem you have

Anything that shows live frame rate, ping and CPU temperature answers that in one match, which is more useful than any amount of boosting done blind.

What to look for

It reports real numbers, including bad ones

This is the single most reliable signal. An honest booster sometimes tells you it freed very little, because on a modern phone that is frequently the truth. An app that reports a large, satisfying figure every single time is showing you an animation with a random number attached.

Test it: run a boost twice in thirty seconds. The second run has almost nothing left to close, so an honest app will report far less the second time. If both runs claim hundreds of megabytes, the number is decorative.

It is specific about mechanism

"Optimises your device for gaming" means nothing. Look for descriptions you could verify: closes background processes, changes the DNS resolver, reads the CPU temperature sensor. Vague verbs usually mean there is nothing underneath them.

The permissions match the claims

A booster needs very little. Usage access to see running apps and, if it offers DNS routing, the VPN permission. If it wants your contacts, your location, your SMS or your photos, those are for advertising, not performance.

The ads do not outweigh the app

Most free boosters are ad-supported, which is fair. What is not fair is an interstitial between every screen, or a "boost" that exists mainly to give you an ad to watch afterwards. If you tap more ads than buttons, the product is the ad.

Claims that are always false

None of the following is possible on Android, by any app, regardless of what the store listing says. Seeing one of these is enough on its own to move on.

"Adds RAM" or "increases CPU speed". No installable app changes your hardware or its clock limits.
"Cools your phone." Software cannot remove heat. A snowflake animation and a lower reading a moment later is not cooling, it is a fluctuating sensor.
"Reduces your ping by 60 percent." Latency is set by distance, routing and congestion. See what ping actually is.
"Unlocks 90 or 120 FPS on any device." Frame rate caps are set by the game and your panel. Config files that claim otherwise are a ban risk, not a feature.
"Frees 2 GB of junk." That figure is usually your game caches, which are not junk and which deleting makes your next load slower.

A short checklist

Does it report different numbers on two consecutive runs?
Can you describe its mechanism in one concrete sentence?
Do the permissions match that mechanism?
Does it claim anything from the list above? Move on if so.
Is your phone 4 GB or less? If not, expect a small effect at best.
Have you tried the built-in game mode first?

So what is the best one?

For most people on a recent phone, honestly: none, and the effort is better spent on graphics settings and on keeping the device cool. For a phone with 4 GB or less, a booster that closes background apps and tells you the truth about what it reclaimed is worth having, and any app meeting the checklist above qualifies.