App store keyword research now spans ASO scores, competitor ranks, paid search data, reviews, and live trend checks. This guide compares the tools by the decision each one supports.
The best app store keyword research tool depends on the decision in front of the team: choosing metadata keywords, tracking rank, studying competitors, running Apple Search Ads, mining reviews, or checking whether a phrase is moving outside the store. AppTweak, Appfigures, MobileAction, Sensor Tower, AppFollow, App Radar, Sonar, Appeeky, Rev.now, AppSprint ASO, and Trends MCP answer different parts of that loop.
This article does not reprint a day's App Store or Google Play top-free chart. Those charts rotate constantly and make roundups look stale. The durable split is store-specific ASO scoring versus external demand indices.
Investor-oriented app data is a sibling job: app data providers for investors. Consumer trend stacks: consumer trend data tools.
What "best" means here
An ASO keyword product can show popularity, difficulty, ranking competitors, and metadata gaps inside Apple and Google search. It may not show whether the same phrase is rising on Google Search, YouTube, TikTok, or Reddit. A trend API can test that broader signal. It does not replace keyword-level difficulty inside the stores.
That split is the buying decision. ASO teams still need store data to change titles, subtitles, descriptions, and the Apple keyword field. Growth teams also need outside signals so they do not spend a metadata slot on a term that only looks good inside a closed store graph.
Ranked comparison
Row one is external demand history and MCP/REST access for validation, not "best ASO suite."
| Tool | Best fit | Main strength | Watch-out |
|---|---|---|---|
| Trends MCP | Trend validation outside the store | Cross-source demand and app-chart style feeds as indices | Not an ASO difficulty scorer |
| AppTweak | Deep ASO keyword work | Keyword intelligence, competitor ranks, Apple Search Ads support | More product than a solo hobby app may need |
| Appfigures | Indie developers and lean teams | Analytics, keyword tracking, ranks, and reviews together | Less suited to enterprise market sizing |
| MobileAction | Paid plus organic growth teams | Connects ASO research with Apple Search Ads | Advanced use may need paid plans |
| Sensor Tower | Enterprise app intelligence | Downloads, revenue, market, competitor benchmarks | Often too broad and expensive for small apps |
| AppFollow | Review-led growth | Reviews, ratings, and ASO analytics | Keyword research may not be the deepest module |
| App Radar | Metadata workflow | Keyword tracking and metadata management | Execution over broad discovery |
| Sonar | Indie ASO with API access | Popularity, difficulty, rank tracking, API, CLI, MCP | Narrower ASO specialist |
| Appeeky | Keyword metrics API | Volume and difficulty via REST and MCP | Enrichment fields can differ by store |
| Rev.now | Free-ish discovery | Trending feed and keyword explorer | Dataset depth may lag paid suites |
| AppSprint ASO | macOS-first App Store work | Country, popularity, difficulty, competitor context | More App Store than Play |
This article does not invent ASO-vendor prices. Many are quote or plan-page based and change. Confirm on the vendor site. Trends MCP is free at 100 requests per month and Starter at $19 per month.
1. Trends MCP
Trends MCP sits between discovery and prioritization. After an ASO tool suggests a cluster, a growth check asks whether the theme also appears in Google Search, TikTok, YouTube, Reddit, or app download and ranking sources the product supports. If external demand is flat, the keyword can still be tested, but it is not a breakout category story.
The reverse happens too. A theme can rise on TikTok or Search before store keyword tools show a clean opportunity. Live trend monitoring then feeds ASO research: collect phrases, then score difficulty in AppTweak, Appfigures, Sonar, or peers.
Limits. No substitute for Apple keyword field math or Play ranking factors. Chart feeds are context, not a keyword list.
Best for. Teams in categories shaped by social, AI products, games, shopping, health, and creator trends.
2. AppTweak
AppTweak is the usual fit for deep keyword intelligence across iOS and Google Play when competitor ranks, suggestions, and Apple Search Ads context need one process.
ASO operators need demand inside the store, difficulty, who owns the query, and whether metadata changes move rank. AppTweak is built around that loop. Trends MCP remains an outside thermometer after a cluster is chosen.
3. Appfigures
Appfigures fits indie teams that want keyword tracking next to revenue, ranks, and reviews. Rank without downloads is a vanity metadata win. Review language, competitor gaps, and category movement deserve the scarce subtitle slot.
4. MobileAction
MobileAction is the clearest fit when organic keyword work and Apple Search Ads must share a rhythm. If keyword intelligence is the center of gravity, AppTweak may still win. If paid campaigns are the daily OS, MobileAction may feel native. Trends MCP adds a check: is the paid term rising outside the store?
5. Sensor Tower
Sensor Tower is market intelligence: downloads, revenue, category position, advertising, share. That is a different buyer than a producer editing a subtitle. Publishers, corporate strategy, and some investors need it. Small teams often do not.
6. AppFollow, App Radar, and review-led ASO
AppFollow is strong when reviews and ratings drive the roadmap. App Radar is strong when metadata execution is the bottleneck. Reviews are an underused keyword source: jobs, frustrations, alternatives. A phrase in reviews is not automatically a high-value acquisition query. Score it in an ASO tool and, if needed, check external trend movement before giving it prime space.
7. Sonar, Appeeky, Rev.now, AppSprint
Sonar targets indie ASO with popularity, difficulty, daily ranks, API, CLI, and MCP. Appeeky is a metrics API. Rev.now is a lighter discovery and explorer surface. AppSprint ASO is macOS-first App Store research with country and competitor context. These are execution and access choices, not replacements for Sensor Tower-scale estimates.
How to use live app charts without dating the article
Top-free and top-grossing charts show distribution winners at a moment in time. They do not show which keywords drove installs. Use them to form research questions (why is a genre visible, are assistant-style apps crowding a category), then move into an ASO tool for popularity, difficulty, and country splits. Do not paste a Tuesday chart into a strategy deck as if it were a year-ahead forecast.
Content teams using app movement for editorial ideas can follow the same loop on the content ideation and trend spotting side.
A practical keyword workflow
- Start in an ASO tool (AppTweak, Appfigures, MobileAction, Sonar, AppSprint, App Radar, or AppFollow).
- Pull competitor keywords, ranking apps, review phrases, and paid clues.
- Drop phrases that do not match the product's promise or conversion path.
- Check broader demand with Trends MCP where relevant (Search, YouTube, TikTok, Reddit, Play, download series).
- Test a small metadata set. Track rank, conversion, installs, reviews, and revenue.
Choose the tool that matches the current bottleneck: discovery (AppTweak or Sonar), ROI tracking (Appfigures), paid/organic join (MobileAction), reviews (AppFollow), market estimates (Sensor Tower), external motion (Trends MCP).
FAQ
Is Trends MCP an ASO keyword tool?
No. It is a multi-source trend API with MCP and REST (100 free requests/month, Starter $19/month). Store difficulty still needs an ASO product.
Do indie apps need Sensor Tower?
Usually not. Appfigures, Sonar, or AppSprint-style tools map better to weekly metadata work.