Comparison

Bubbles TD vs Collect Letters!

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

Head to head

About

Bubbles TD

Features

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Like Tower Defense? Give our game a try. The objective of the game is to install your weapons to prevent the bubbles travelling along the path from reaching the end. Use coins, earned by shooting bubbles, to buy new weapon and upgrade existing ones. Watch out against the BOSS bubble – it has multiple lives and shoots back at your weapons. Choose between different routes and different difficulty levels. Don't forget to check our Game section for other fun games...

About

Collect Letters!

Features

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· TAP the letters to complete the words · DEAL cards for new letters · RELAX and ENJOY this casual puzzle game

Screenshots

Bubbles TD4 screens

Collect Letters!4 screens

Verdict

The call

The clearest difference is in-app purchases: Bubbles TD at none against Collect Letters!'s 10. Bubbles TD also leads on iOS requirement (9.0 vs 12.0). On price, update cadence, ads 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. Collect Letters! sells 10 one-off in-app purchases. Bubbles TD asks for nothing beyond the download.

UpkeepUpdate frequency

Both ship on a similar rhythm, roughly every 17 months. The most recent releases landed on October 26, 2026 and October 7, 2026 respectively.

Scorecard2 real differences · 4 level

Bubbles TD versus Collect Letters!: the parameters behind the verdict, then further details
Parameter	Bubbles TD	Collect Letters!
Price	Free	Free
Update frequency	Every 17 months	Every 17 months
Ads	Yes	Yes
In-app purchases	No — better	Yes
Devices	iPhone, iPad, iPod	iPhone, iPad, iPod
Requires iOS	9.0 — better	12.0
Further details — not scored
Size	14 MB	157 MB
Age rating	4+	4+
Developer	GASP Mobile Games Inc	Rootcraft

In-app purchases

None

Bubbles TD

No in-app purchases

10 purchases

Collect Letters!

One-time10

3,000 Gems$1.99
1,500 Cards$1.99
1,000,000 Coins$1.99

Show 7 more

5,000 Gems$2.99
8,000 Cards$3.99
8,000 Gems$3.99
16,000 Gems$4.99
60,000 Cards$5.99
50,000 Gems$5.99
120,000 Gems$6.99

Questions

Is Bubbles TD free?

Bubbles TD is free to download, with no in-app purchases.

Is Collect Letters! free?

Collect Letters! is free to download, with in-app purchases available.

Do Bubbles TD or Collect Letters! have ads?

Both Bubbles TD and Collect Letters! show ads.

Which is updated more often, Bubbles TD or Collect Letters!?

Bubbles TD ships an update every 17 months, and Collect Letters! every 17 months. Most recently, Bubbles TD was updated on October 26, 2026 and Collect Letters! on October 7, 2026.