Comparison

Instock vs Harpy Alerts

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

Instock

Never miss a product drop or restock again. This assistant notifies you in real-time when items become available across hundreds of retailers. Customize your feed with desired products or focus on discounts.

Highlights
  • Real-time restock notifications
  • Customizable product feed
  • Discounts-only feed
  • Live release feed
  • Direct add-to-cart links
  • Autofill for faster checkout
Read full description

YOUR PERSONALIZED SHOPPING ASSISTANT Get the instock app and start shopping in real-time! Select your products of interest, build your customized product feed, and you're all set to never miss a drop or restock. You'll receive notifications as your items of choice are made available across hundreds of retailers. You can also browse our discounts-only feed that exclusively shows discounted products. --- REAL-TIME NOTIFICATIONS Get alerts for the products that matter to you, right when they are available. EXTENSIVE PRODUCT SUPPORT From sneakers to consoles, clothing to electronics, sports equipment or home goods, we aim to facilitate your purchases, whatever the item is. We constantly update our product catalogue to support user requests and latest trends. LIVE RELEASE FEED See product drops and restocks as they happen. CUSTOMIZED PRODUCT FEED Build your personalized product feed based on the items you are looking for. DISCOUNTS-ONLY FEED Filter through on-sale drops and restocks and find steals. FASTER PURCHASES Speed up checkouts using direct add-to-cart links and autofills (premium features). --- Upgrade to instock Premium - Unlock up to 50 different products for your personalized product feed. - Receive prioritized notifications 45 seconds before free users. - Get add-to-cart links for hundreds of sites, directly in the monitors and custom product feeds. - Save time at checkout with autofill - Enjoy an ad-free experience by getting rid of display banners on every tab. Premium subscription notes - Subscription is currently exclusively available via Apple. - Subscription will be charged to your App Store account. - Subscription renews unless you disable renewal at least 24 hours prior to the renewal. - Apple charges subscription renewal around 24 hours prior to the end of the current subscription period. - Subscription can be managed directly from the App Store > My Account > Subscription. --- Terms & Conditions: https://getinstock.app/terms Privacy Policy: https://getinstock.app/privacy

About

Harpy Alerts

Features
Read full description

Turn the eBay searches you care about into Hunts. Harpy keeps track of what it has already seen, highlights new results, and helps you focus on what has changed. START A HUNT Search using keywords, categories, condition, price and seller filters. Preview matching listings before starting your Hunt so you know you're watching the right search. SPOT NEW LISTINGS Harpy keeps track of what it has already seen. When new matching listings appear, they're clearly identified so you can focus on what's changed instead of searching through the same results again. GET ALERTED Your Hunts continue checking automatically. When Harpy finds new matches, it can send you a notification so you don't have to keep opening eBay and repeating the same search. AUCTION ENDING REMINDERS Enable reminders for matching auctions Harpy discovers before their reminder time, giving you another chance to check an item before bidding closes. MAKE IT YOURS Add personal notes to Hunts, edit your search criteria, and pause or resume monitoring whenever you like. Set Quiet Hours to silence notifications while your Hunts continue checking. Harpy requires an account and is intended for adults aged 18 and over. Purchases and bids take place on eBay. Harpy does not place bids or complete purchases for you.

Screenshots

Instock4 screens
Harpy Alerts4 screens

Verdict

The call

The clearest difference is in-app purchases: Harpy Alerts at none against Instock's 1. Harpy Alerts also leads on ads (none vs shown) and update cadence (every 3 days vs every 4 weeks). Instock's advantage is iOS requirement (13.0 vs 18.5). On price and device support there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. Instock sells 1 in-app purchase, starting at $9.99 per month. Harpy Alerts asks for nothing beyond the download.

UpkeepUpdate frequency

Instock ships an update every 4 weeks, Harpy Alerts every 3 days. The most recent releases landed on October 30, 2026 and October 26, 2026 respectively.

Scorecard4 real differences · 6 level
Instock versus Harpy Alerts: the parameters behind the verdict, then further details
ParameterInstockHarpy Alerts
PriceFreeFree
Rating4.7 (15 ratings) — better—
Positive reviews75.0% of reviews—
Number of ratings15 — better—
Update frequencyEvery 4 weeksEvery 3 days — better
AdsYesNo — better
In-app purchasesYesNo — better
MonetizationFree with in-app purchases—
DevicesiPhone, iPodiPhone, iPad
Requires iOS13.0 — better18.5
Further details — not scored
Size38 MB8 MB
Age rating4+17+
DeveloperJNJ Software LTDAndy Geer

In-app purchases

1 purchases

Instock

Subscriptions1
  • Premium Subscription$9.991 Month
None

Harpy Alerts

No in-app purchases

Questions

Is Instock free?
Instock is free to download, with in-app purchases available.
Is Harpy Alerts free?
Harpy Alerts is free to download, with no in-app purchases.
Do Instock or Harpy Alerts have ads?
Instock shows ads; Harpy Alerts does not.
Which is updated more often, Instock or Harpy Alerts?
Instock ships an update every 4 weeks, and Harpy Alerts every 3 days. Most recently, Instock was updated on October 30, 2026 and Harpy Alerts on October 26, 2026.

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