PlanetWeight vs Kaira

PlanetWeight invites you to the thrilling exploration of weight variations across the universe! Easily calculate your weight on 9 different celestial bodies, including Mercury, Venus, Moon, Mars, Jupiter, Saturn, Uranus, Neptune, Pluto, and even the Sun.  Simply input your own weight, and PlanetWeight instantly provides weight values for each celestial body.  Delve into the app for insights on weight differences. By using your Earth weight as a reference, understand the relative weight contrasts across other celestial bodies. Embark on a cosmic journey with this unique experience and uncover your weights on other planets!

Kaira: Math — gentle math practice for ages 7–9 Meet Kaira, a friendly Samoyed who keeps your child company during math practice. Kaira: Math is a calm, ad-free arithmetic app built on what cognitive science actually says about how kids learn math — not on points, streaks, or pressure. A DIFFERENT KIND OF MATH APP Most kids' math apps use coins, scores, and leaderboards to keep children engaged. Research on child motivation shows these rewards can actually reduce a child's interest in learning over time. Kaira: Math takes a different path. Children progress by building real skill, one step at a time, with Kaira by their side. HOW IT WORKS Your child chooses a skill to practice and how many problems to solve: 5, 10, or 15. Each skill has two phases: - Learning mode — calm, untimed, with gentle hints when something feels hard. Mistakes are treated as information, not failures. - Fluency mode — unlocks only after your child is consistently accurate. A playful way to build speed once the foundation is solid. New skills unlock automatically as earlier ones are mastered. No skill is ever forced, no skill is ever skipped. WHAT YOUR CHILD PRACTICES 25 carefully sequenced addition and subtraction skills, from single-digit facts through three-digit problems with carrying and borrowing. The progression is built on evidence-based strategies like "making tens" and decomposition — the same techniques great teachers use. THE PARENT DASHBOARD Behind a PIN, parents get a dashboard that shows what really matters: which skills your child is working on, where they are stuck, and what kind of mistakes they are making. Not just "73% correct" but "most errors are forgotten carries" — with specific suggestions for how to help at home. PRIVATE BY DESIGN - All data stays on your device. No accounts, no cloud, no sign-up. - No ads. Ever. - No analytics or tracking of your child. - No network connection required to use the app. FOR AGES 7–9 Designed for children in roughly 2nd through 4th grade who are working on double-digit addition, subtraction, carrying, and borrowing. Kaira: Math is not a replacement for school math — it is a calm, private place to build fluency and confidence between lessons. SUBSCRIPTION Kaira: Math Premium unlocks full access to all skills and the parent dashboard. Try it free for 7 days, then $4.99/month or $29.99/year. Cancel anytime in your Apple ID settings. Payment is charged to your Apple ID at confirmation of purchase. Subscription automatically renews unless cancelled at least 24 hours before the end of the current period. Practice math with Kaira. One skill at a time. Terms of Use: https://spartak.io/kaira_math/terms.html