ASO Glossary
App Metadata
App metadata refers to all the textual and visual elements that describe your app in the App Store — including the title, subtitle, keyword field, description, icon, and screenshots.
What Is App Metadata?
App metadata is the collection of textual and visual elements that describe your app in the App Store. It's everything a potential user sees before downloading — and everything the search algorithm uses to determine when your app appears in search results. Optimizing app metadata is the core activity of App Store Optimization.
iOS App Store Metadata Fields
Apple's App Store has specific metadata fields, each with different search-indexing weight, character limits, and visibility to users:
Indexed, User-Visible Fields
| Field | Character Limit | Search Weight | Notes |
|---|---|---|---|
| App Title | 30 characters | Highest | Most important field for both search ranking and user first impression |
| Subtitle | 30 characters | High | Displayed below the title in search results. Second-strongest search signal |
Indexed, Hidden Field
| Field | Character Limit | Search Weight | Notes |
|---|---|---|---|
| Keyword Field | 100 characters | Moderate | Hidden from users. Comma-separated, single words only. Most flexible field for keyword experimentation |
Not Indexed for Search (but affects conversion)
| Element | Impact |
|---|---|
| App Icon | First visual impression. Heavily influences tap-through rate |
| Screenshots | Visual preview of app features. Critical for conversion |
| Description | Detailed feature explanation. Read by users who tap into the product page. Not directly indexed by Apple's search algorithm on iOS |
| App Preview Videos | Optional video showcasing the app in use |
| Ratings & Reviews | Star rating and user reviews. Influences both search ranking and download decisions |
The 160-Character Budget
For search optimization on iOS, you have a total of 160 indexed characters: 30 (title) + 30 (subtitle) + 100 (keyword field). Every character counts. The key principle: each word only needs to appear once across all three fields. The search algorithm combines words from different fields to match multi-word queries.
This means your optimization strategy is about maximizing the unique searchable vocabulary across 160 characters — not about repeating important keywords across fields.
Metadata Optimization Strategy
- Research keywords first. Before writing metadata, identify your target keywords based on popularity, difficulty, and opportunity score.
- Place highest-value keywords in the title. Title keywords carry the most ranking weight. Use your strongest, most relevant keyword here.
- Use the subtitle for second-tier keywords. Keywords that don't fit in the title but need to be both indexed and user-visible go here.
- Fill the keyword field with remaining terms. Sweet Spots, Hidden Gems, and supplementary keywords go in the keyword field. Use all available space — aim for 90+ characters.
- Localize for each market. Different title, subtitle, and keyword field for each language/market you target.
Metadata vs. Performance Signals
Metadata is the foundation of ASO, but it's not the only ranking factor. The App Store algorithm also considers:
- Download velocity: How many people download your app in a given period
- Ratings and reviews
- User engagement: Retention, session length, uninstall rate
- Update frequency: Regularly updated apps may receive a ranking boost
Metadata gets your app into search results. Performance signals determine where it ranks among competitors targeting the same keywords.
Common Metadata Mistakes
- Treating metadata as a one-time task. The competitive landscape changes constantly. Quarterly metadata reviews keep your keywords competitive.
- Prioritizing branding over keywords. "AppName — For a Better Tomorrow" scores zero relevant keywords. "AppName: Budget & Expense Tracker" scores several.
- Using the description for keyword stuffing. Apple doesn't index the iOS description for search. Keyword-stuffed descriptions waste effort and read poorly.
- Same metadata for all markets. English metadata in Japan or Brazil misses the vast majority of searches conducted in local languages.
How RespectASO Supports Metadata Optimization
RespectASO provides the keyword data needed to make informed metadata decisions. Score potential keywords on popularity, difficulty, and opportunity across 30 markets, then allocate the highest-value terms to your title, subtitle, and keyword field. The classification system highlights Sweet Spots and Hidden Gems — the keywords that deserve priority placement in your limited 160-character budget.
Put This Knowledge Into Practice
Use RespectASO to research keywords and optimize your App Store metadata.