Last updated: 24/07/2026
The short answer
App Store Optimization is the practice of getting the fields on your App Store and Google Play listing right so that the people searching for an app like yours actually find it — and, once they land on your page, tap "Get". It is not guesswork. Both stores publish the exact character limit of every field and state, in their own documentation, which parts of your listing feed search and which do not. That means an owner who has never written a line of code can still hold a vendor to a checklist: the right words in the fields that count, and the visuals tested rather than guessed.
The two stores are close cousins but not identical, and the differences matter. On Apple's App Store, your app name (two to thirty characters) and subtitle (up to thirty characters), together with a hidden 100-byte keywords field, carry the search relevance — while your description, however good, is not indexed for search at all. On Google Play, by contrast, the store-listing text as a whole feeds discovery. Get those fields wrong and you can build a genuinely good app that no one ever sees; get them right and you have given every marketing dollar behind it a fighting chance.
What ASO actually is — and what it cannot do
ASO is the store-listing equivalent of SEO: the ongoing work of shaping the words, images and signals on your app's product page so the store's own search surfaces it to the right people. It is a growth lever you own outright — no media budget required — and unlike paid installs, the value compounds every time someone searches. But it is worth being honest about its ceiling, because over-promising here is exactly the kind of claim we will not make: ASO improves how discoverable and how convincing your listing is; it does not turn a weak app into a strong one, and neither store will tell you a guaranteed ranking formula. What they do publish is the raw material — the fields, their limits, and the factors that feed search — and that is enough to work with.
The mental model that helps most owners is to split the listing into two halves. The first half is found: the text fields that determine whether your app appears when someone searches. The second half is chosen: the icon, screenshots and preview video that determine whether a person who sees your listing actually installs. ASO done well works both halves — the right keywords to get found, then the right visuals to get chosen — and, crucially, the tools to improve the second half are free and built into both consoles.
The App Store fields that carry search weight
On Apple's App Store, a small number of short fields do the heavy lifting for search, and the longer fields you might expect to matter — the description especially — do not feed it at all. This is the single most common ASO mistake we see: teams pour keywords into a beautifully written description that Apple never indexes, and leave the 100-byte keywords field half-empty. Apple documents the limit of every field precisely, so there is no need to guess.
| Field | Limit (Apple's own words) | Shown to users? | Feeds search? |
|---|---|---|---|
| App name | "at least two characters and no more than 30 characters" | Yes — the headline of your listing | Yes (title text relevance) |
| Subtitle | "can't be longer than 30 characters" | Yes — under the name | Yes (subtitle text relevance) |
| Keywords | "up to 100 bytes of content" | No — visible only to you | Yes (keyword text relevance) |
| Promotional text | "can't be longer than 170 characters" | Yes — top of the description, editable anytime | No — "doesn't affect your app's search ranking" |
| Description | "Limited to 4000 characters" | Yes — the full pitch | No (not indexed for search) |
| What's New | "Limited to 4000 characters" | Yes — per version | No |
Two practical rules fall out of that table. First, the keywords field is measured in bytes, not characters, and Apple's guidance is to separate terms with commas and no spaces to make every byte count — an accented or non-Latin character can consume more than one byte, which matters if you localise. Second, because promotional text is not indexed but can be edited without shipping an app update, treat it as your changeable marketing banner (a sale, a new feature) rather than a place to stuff keywords, which is exactly what Apple tells you not to do.
The same fields on Google Play
Google Play uses a different set of fields, and it treats the store-listing text as a whole as a discovery signal rather than isolating a hidden keyword box. Google's Play Console Help sets the limits plainly: the app name is capped at 30 characters, the short description at 80, and the full description at 4,000 — and it notes those "limits apply to both full-width and half-width characters", so a Chinese or Tamil localisation gets the same character budget as an English one. Because Google states that "the text in your store listing helps users discover your app", the full description is genuinely worth writing for humans and search together, which is the opposite of Apple's not-indexed description.
| Purpose | Apple App Store | Google Play |
|---|---|---|
| The name people see | App name — 2–30 characters | App name — 30 characters |
| One-line hook | Subtitle — 30 characters | Short description — 80 characters |
| The full pitch | Description — 4,000 characters (not indexed for search) | Full description — 4,000 characters (feeds discovery) |
| Dedicated keyword field | Keywords — 100 bytes, hidden from users | None — keywords live in the visible text |
| Editable marketing line | Promotional text — 170 characters, not ranked | Handled within short/full description |
For a Singapore team the storefront that matters is the local one — the Singapore App Store and the Singapore Google Play storefront, both of which default to English. If you plan to expand across South-East Asia, both stores let you add localised listings per country and language, and both count characters generously enough that a Bahasa Indonesia or Thai listing gets the same field budget as your English one. Localise the words a real customer would search in each market, not a machine translation of your English keywords.
What actually ranks your app in search
Both stores are explicit that text is only half the story: the other half is how real users behave once your app is live. Apple states its search results are "based on a number of factors, including text relevance (matches for your app's title, subtitle, keywords, and primary category), as well as user behavior (downloads, ratings and reviews, and more)". Google's discovery guidance points the same way, weighing "ratings, reviews, downloads, and other factors" alongside the listing text. In other words, the metadata gets you into the running; downloads and reviews decide the race.
That has a blunt implication for planning. No amount of keyword tuning outruns a one-star average, and the fastest way to earn the reviews that lift ranking is to ask for them inside a genuinely good experience — which loops ASO back to product quality and to the health metrics we cover in measuring app success after launch. Your primary category also carries real weight in Apple's list of relevance signals, so choosing the category your customers actually browse — rather than the most flattering one — is an ASO decision, not an afterthought. And getting through review to be listed at all comes first: our App Store submission checklist for Singapore covers that gate.
Testing your listing: A/B tools both stores give you free
The second half of ASO — getting the person who sees your listing to install — is where both stores hand you a free experimentation tool, and far too few small teams use them. Apple's Product Page Optimization lets you compare up to three alternate versions of your product page — different app icons, screenshots and app previews — against your original, and read the results in App Analytics. Apple shows you conversion rate, percent improvement and a confidence level, and tells you how many impressions you would need to reach "at least 90% confidence"; a test runs for up to 90 days or until you stop it, and you then set the best performer live for everyone.
Google Play offers the equivalent through store-listing experiments — a default graphics experiment on your icon, feature graphic and screenshots, or up to five localized experiments testing icon, graphics, screenshots and descriptions across up to five languages, with up to two variants tested against your current listing. The console reports which option performs best against your target metric. The discipline to insist on is the same on both platforms: change one thing at a time (icon, or first screenshot, or subtitle wording — not all three), let the test reach the store's own confidence threshold before you believe it, then promote the winner.
| Capability | Apple — Product Page Optimization | Google Play — store-listing experiments |
|---|---|---|
| What you can test | App icons, screenshots, app previews | Icon, feature graphic, screenshots; descriptions (localized experiments) |
| Variants per test | Up to 3 treatments vs the original | Up to 2 variants vs the current listing |
| Localisation | Per localised product page | Up to 5 localized experiments, up to 5 languages |
| How results are read | App Analytics: conversion, % improvement, "at least 90% confidence" | Console reports the best option against your target metric |
| Duration | Up to 90 days or until stopped | Runs until it reaches a result / is stopped |
A pre-launch ASO checklist for a Singapore app
ASO is cheapest when it is decided before launch, because renaming an app or re-shooting screenshots after the fact is far more disruptive than getting them right the first time. Here is the short list we work through with a client during scoping, framed as questions an owner can ask a vendor and expect an evidenced answer to:
- Does the app name earn its 30 characters? The brand plus one or two words describing what the app actually does — not the brand alone. On both stores the name is your strongest search field.
- Is the App Store subtitle and the Play short description written for a searcher, not a slogan? Thirty characters (Apple) and eighty (Google) are enough for a concrete benefit, not a tagline.
- Is the 100-byte App Store keywords field full — and free of words already in your name? Repeating a word you already rank on wastes bytes; use them for the terms customers type that are not in your visible fields.
- Is the primary category the one your customers browse? Apple counts it as a relevance signal; pick the honest, high-intent category, not the prettiest one.
- Do the first two or three screenshots make the value obvious without reading? These show in search results on both stores, so they are doing ASO work before anyone opens your page.
- Is there a plan to earn reviews inside the app? Downloads and ratings are ranking factors on both stores; a review prompt at the right moment is part of ASO, not separate from it.
- Are the free A/B tools switched on for the first month? Set up one Product Page Optimization test and one Play store-listing experiment from day one, and let the data replace opinion.
What ASO costs, and how Namtech handles it
The tools themselves cost nothing — the metadata fields, App Analytics, Product Page Optimization and Play store-listing experiments are all included with your developer account. What ASO costs is thought and iteration, and at Namtech that work sits inside the launch and the maintenance window rather than as a separate invoice. Our published tiers start at SGD 20,000 for a Starter / MVP, SGD 38,000 for a Business app and SGD 90,000 for an Enterprise / Platform build, with every project scoped individually — honest starting points, not teaser rates. Store-listing setup, keyword research for your category and the first round of screenshots are part of getting an app live, the same way passing review is.
After go-live, ASO becomes an ongoing habit rather than a one-off, which is why it pairs naturally with maintenance and support from 15% of build cost per year: as you learn which searches convert, you refine the fields and run the next A/B test. We will not quote you a "guaranteed ranking" or a download-uplift percentage, because neither store publishes a formula that would let anyone promise one honestly — what we will do is set the fields to the published limits, switch on the free experiments, and iterate on real numbers.
App Store Optimization is not a growth-hack secret — it is a handful of fields with published character limits and two free A/B tools, and the teams that win are simply the ones who fill them in deliberately instead of leaving them to chance.
Sources
- Apple — App information (App Store Connect Help reference): app name "at least two characters and no more than 30 characters"; subtitle "can't be longer than 30 characters".
- Apple — Platform version information (App Store Connect Help reference): keywords "up to 100 bytes of content"; promotional text "can't be longer than 170 characters"; description and What's New "Limited to 4000 characters".
- Apple — App Store search: "Search results are based on a number of factors, including text relevance (matches for your app's title, subtitle, keywords, and primary category), as well as user behavior (downloads, ratings and reviews, and more)"; "promotional text doesn't affect your app's search ranking".
- Apple — Product Page Optimization: "Test up to three alternate product page versions against your original"; app icons, screenshots and app previews; results in App Analytics with "at least 90% confidence"; runs up to 90 days.
- Google — Create and set up your app (Play Console Help): app name "30 character limit"; short description "80 character limit"; full description "4000 character limit".
- Google — Run A/B tests on your store listing (Play Console Help): default graphics experiment (icon, feature graphic, screenshots) or "up to five localized experiments at the same time"; "up to 2 variants"; up to five languages.
- Google — Get discovered on Google Play search (Play Console Help): "The text in your store listing helps users discover your app"; ratings, reviews and downloads among ranking factors; localisation aids discoverability.
- Namtech — Pricing (SGD 20,000 / 38,000 / 90,000; Maintenance & Support from 15% of build cost per year).