App Store Keyword Research: South Korea

South Korea is a high-revenue market for games and productivity apps with moderate difficulty compared to Japan for the same categories.

Korean-language keywords are mandatory — transliteration of English product names into Hangul is common but must be phonetically accurate.

South Korea is one of the storefronts where difficulty does the deciding. Demand is deep enough that almost any sensible term returns volume, and the question is which of them you can realistically reach.

1. Build the candidate list in Korean. Translating an English list is the common mistake. Pull the terms from South Korea App Store listings and from what competitors put in their subtitle, because Korean search habits rarely map word for word onto English ones.
2. Score for popularity in this storefront specifically. Popularity is calibrated per storefront, so a term that scores 60 here is genuinely deep demand. Above 25 is the floor worth spending characters on.
3. Check difficulty. Filter to difficulty below 60 for an established app and below 45 for a new one. In a market this size the top slots are held by apps with years of install history behind them.
4. Write the metadata for South Korea. Korean is used by this storefront alone, so this metadata does one job and can be tuned to it without trading anything off.

• App Name, 30 characters. Your brand plus the single highest-demand term you can defend in South Korea. This field carries the most ranking weight of the three, so it takes the term you most want and can plausibly reach, not the one with the biggest popularity score.
• Subtitle, 30 characters. Two or three secondary terms in Korean. It is indexed and it is also the line a searcher reads before deciding to tap, so it has to survive being read as a sentence by a Korean speaker.
• Keyword field, 100 characters. Korean is compact in the keyword field, fitting 20 to 30 terms, but compound nouns are written closed. Include both the joined and the spaced form of any two-word concept, since users type both. Never repeat a word already used in the name or subtitle; those are indexed already, and the field is the one place where a wasted character is a term you could have had.

Most localisation decisions are made across a group of storefronts: one Spanish keyword field is indexed in fifteen markets, one Arabic field in fourteen. Korean is not one of those. The work you do here earns its return in South Korea alone, so the market has to justify the translation on its own.

It usually does. Difficulty is measured against the apps that bothered to localise, and in a single-language market that set stays small, so the terms stay reachable for longer than volume alone would suggest.