Methodology

Mobile App Glossary: Key Terms for Indie Developers (2026)

A reference glossary of every important term indie mobile developers should know — ASO acronyms, monetization concepts, attribution terminology, and more.

ASOhack TeamMay 19, 20266 min read

A reference glossary. Bookmark this for terms you've heard but want clear definitions of.

ASO terms

ASO

App Store Optimization. The practice of improving an app's visibility and conversion rate in the App Store and Google Play Store.

Conversion rate

% of users who install after viewing your product page.

CR (Conversion Rate)

Same as above.

CTR (Click-Through Rate)

% of users who tap your app in search results.

Impressions

Number of times your app appeared in search / browse.

Product page views

Number of users who clicked through to your app's product page.

Keyword density

How often a keyword appears in your listing relative to total words.

Keyword stuffing

Over-using keywords. Penalized by algorithms.

Keyword field

iOS-only field (100 chars) for keywords invisible to users.

Title

Your app's name as displayed in the store (30 chars iOS, 30-50 Android).

Subtitle

iOS-specific second line under your app title (30 chars).

Short description (Android)

Equivalent to iOS subtitle, but 80 chars.

Long description

The full app description, 4,000 chars max.

App Store Connect

Apple's developer portal for managing your iOS app listing.

Google Play Console

Google's developer portal for managing your Android app listing.

Featured

When App Store / Google Play editorial chooses to highlight your app.

Editor's Choice

Google Play badge for editorial-selected apps.

App preview video

iOS-specific 15-30 second video shown on your product page.

Equivalent on Google Play.

Localization

Adapting your listing for non-English / non-US markets.

Translation

Different from localization — just changing language without cultural adaptation.

In-App Events (iOS)

Time-bound events shown in App Store search, since iOS 15.4.

Custom Product Pages (CPPs)

Apple Search Ads feature allowing different product pages per ad group.

A/B testing

Running two variants (icon, screenshot, video) against each other.

Conversion lift

Improvement in conversion rate due to a change.

Monetization terms

IAP (In-App Purchase)

One-time or recurring purchase within an app.

Subscription

Recurring IAP.

Trial

Free period before subscription billing begins.

Trial-to-Paid

Conversion from free trial to paid subscriber.

Paywall

Screen requiring payment to proceed.

Hard paywall

User must pay; can't continue without it.

Soft paywall

User can continue free; paywall offered but not required.

Freemium

Free tier + paid tier.

Net revenue

Revenue after Apple / Google's commission (typically 30%, 15% for Small Business / Year 2+ on subscriptions).

ARPU (Average Revenue Per User)

Total revenue / total users.

LTV (Lifetime Value)

Expected revenue from a user over their lifetime.

Churn

Users canceling subscriptions or stopping using your app.

Voluntary churn

User actively cancels.

Involuntary churn

Card declined; user didn't actively cancel.

Refund

Money returned to user.

Chargeback

Bank dispute resulting in refund.

Acquisition / paid terms

CPI (Cost Per Install)

Total spend / installs from a channel.

CPM (Cost Per Mille)

Cost per 1,000 impressions.

CPC (Cost Per Click)

Cost per ad click.

CPA (Cost Per Action)

Cost per specific action (often paid signup).

CAC (Customer Acquisition Cost)

Total marketing spend / new paying customers.

LTV/CAC

Ratio. Healthy = 3:1+.

ROAS (Return on Ad Spend)

Revenue from ad spend / ad spend. Healthy = 100%+.

Payback period

Months until acquisition is recovered.

D1, D7, D30, D90 retention

% of users still active at day N.

Cohort retention

Retention measured per acquisition cohort.

MAU (Monthly Active Users)

Unique users in 30 days.

DAU (Daily Active Users)

Unique users in 1 day.

Stickiness ratio

DAU/MAU. Higher = more frequently used.

Engagement

Generic term for how often / how much users use your app.

Activation

When user completes core onboarding / first value action.

Attribution terms

Attribution

Identifying which channel / source brought a user.

MMP (Mobile Measurement Partner)

Third-party attribution tools (Adjust, AppsFlyer, Singular).

SKAdNetwork (SKAN)

Apple's privacy-restricted attribution system (since iOS 14.5).

SKAN 4.0

Latest version (as of 2026).

ATT (App Tracking Transparency)

Apple's user permission prompt for cross-app tracking (since iOS 14.5).

IDFA (Identifier for Advertisers)

Apple's advertising ID. Used for tracking; requires ATT consent.

GAID (Google Advertising ID)

Android equivalent of IDFA.

Install referrer

Google Play attribution mechanism (since Android 4.0+).

Deep link

URL that opens your app to a specific screen.

Universal Link (iOS)

iOS-specific deep link mechanism using HTTPS URLs.

App Link (Android)

Equivalent on Android.

Deferred deep link

Deep link that survives the install process (Branch, AppsFlyer handle this).

Privacy / compliance

EU privacy regulation.

CCPA / CPRA

California privacy laws.

COPPA

US privacy law for kids under 13.

Privacy nutrition label (iOS)

Apple's data practices disclosure.

Data Safety section (Android)

Google's equivalent.

Data Subject Rights

User rights to access, delete, port their data.

DPO (Data Protection Officer)

Required EU role for some companies.

Technical terms

Crash-free sessions

% of sessions that completed without crashing.

ANR (Application Not Responding)

Android-specific event where the app freezes.

TestFlight (iOS)

Apple's beta distribution platform.

Internal Testing (Android)