Comparison

Bubbles vs RST 599x

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

Head to head
About

Bubbles

This interactive digital book teaches New Zealand Sign Language and English vocabulary through engaging animations, sound effects, and read-along features. It offers options for children to read independently or with narration, and includes coloring activities for illustrations.

Highlights
  • Swipe-to-Read™
  • Touch-to-Hear™
  • Touch-to-Spell™
  • Read-to-me and read-it-myself options
  • Record narration
  • Color illustrations
  • Animation and sound effects
Features
Read full description

Bubbles by Dot Meharry illustrated by Fraser Williamson This app is intended as a New Zealand Sign Language resource. FEATURES: - Swipe-to-Read™ - Touch-to-Hear™ - Touch-to-Spell™ - Read-to-me and read-it-myself options - Record your narration - Colour in the illustrations - Animation and sound effects - A child-friendly user interface - Parents/Teachers Notes This digital book contains text and audio in English and a video readthrough and vocabulary in NZSL NEED HELP? Contact us: support@kiwadigital.com KIWA® is the world’s leading production house for experiential digital books. We partner with publishers and other content owners, using our patented technology to bring content to life in revolutionary new digital formats that deepen your child’s engagement and understanding. Check out our website: www.kiwadigital.com Find us on Facebook: https://www.facebook.com/KiwaDigital

About

RST 599x

This app simulates real-time CW QSO interactions for amateur radio enthusiasts. It offers various QSO styles, realistic signal conditions, and customizable station settings for an authentic experience. Features include pile-up reproduction and RIT/filter functions.

Highlights
  • CW QSO simulation
  • Pile-up reproduction
  • Multiple QSO styles
  • RIT and CW filter
  • Realistic signal meter
  • Spectrum scope display
Features
Read full description

This app is a real CW QSO simulator for Amateur Radio. "599BK type QSO", "Rubber stamp type QSO" and "Contest type QSO" are supported. In addition, the call sign, signal level, CW speed, etc. that occur differ for each QSO in order to achieve realism. Furthermore, the call sign and CW speed of your own station that issues CQ can be set arbitrarily. 【Characteristic】 1. Reproduction of pile-up (Called from up to 3 stations at the same time) 2. "599BK","Rubber Stamp" and "AADX Contest" style support. 3.RIT and CW filter functions  Band Width(300Hz/600Hz) control supported. 4.Realistic signal meter according to audio signal level. 5.Status display showing TX / RX operation. 6.The spectrum scope display 【Other features】 1. Function to select the number of QSOs to communicate (5, 20) 2. QRN ON / OFF selection function 3. Function to select the call area (JA's, W / W) 4. Judgement of "RST, QRA and QTH" or "RST, QRA and WX" information. 5.Supported the ESC button for escaping from the long TX/RX. 6.Supported the Score Clear button of your Hi-Score Data. 7.Support the capture function of Hi-Score dialog. 8.Supported the QSB in the mode of "599BK / AADX" and "W/W" Supported keyboard input from Apple Silicon Mac. (Not compatible with iOS) [Support Key] A-Z, 0-9, / Enter:return ESC:esc BS:delete CQ:UpArrow AGN:DownArrow TU:[ LEFT:LeftArrow RIGHT:RightArrow

Screenshots

Bubbles4 screens
RST 599x4 screens

Verdict

The call

The clearest difference is price: Bubbles at Free against RST 599x's $1.99. RST 599x's advantage is update cadence (every 2 months vs every 37 months). On ads, in-app purchases, device support and iOS requirement 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

Bubbles is free to download; RST 599x costs $1.99 up front. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

Bubbles ships an update every 37 months, RST 599x every 2 months. The most recent releases landed on November 1, 2026 and November 3, 2026 respectively.

Scorecard3 real differences · 7 level
Bubbles versus RST 599x: the parameters behind the verdict, then further details
ParameterBubblesRST 599x
PriceFree — better$1.99
Rating—5.0 (1 ratings) — better
Positive reviews100.0% of reviews—
Number of ratings—1 — better
Update frequencyEvery 37 monthsEvery 2 months — better
AdsNoNo
In-app purchasesNoNo
MonetizationFree — betterPaid
DevicesiPhone, iPad, iPod — betteriPhone, iPod
Requires iOS13.012.0 — better
Further details — not scored
Size86 MB71 MB
Age rating4+4+
DeveloperMinistry of Educationkoji kamogawa

Customer experience

Bubbles

Written reviews1 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

RST 599x

All ratings1 ratings
Positive100.0%
Neutral0.0%
Negative0.0%

In-app purchases

None

Bubbles

No in-app purchases

None

RST 599x

No in-app purchases

Questions

Is Bubbles free?
Bubbles is free to download, with no in-app purchases.
Is RST 599x free?
RST 599x costs $1.99, with no in-app purchases.
Do Bubbles or RST 599x have ads?
Neither Bubbles nor RST 599x shows ads.
Which is updated more often, Bubbles or RST 599x?
Bubbles ships an update every 37 months, and RST 599x every 2 months. Most recently, Bubbles was updated on November 1, 2026 and RST 599x on November 3, 2026.

Other comparisons