Pure Math Drills vs 少年卫星跟踪台

Pure Math Drills is a fast, focused arithmetic trainer that decides what you should practice next. Open the app and you are already drilling. A short warm-up finds your level, then every problem is chosen from what you know, what is starting to fade and what is next: a stretch, not a slog. • Endless adaptive drill: no menus, no setup, no grade levels • Practice tracks for addition, subtraction, multiplication, division, negative numbers, fractions, decimals, percents, powers and roots, order of operations, and simple equations — turn on any combination in Settings • A visible timer bar on every problem that adapts to your own speed; running out of time never counts as a wrong answer • See exactly which problems you missed after every round, with the correct answers • Missed problems come back a few problems later, and mastered facts return for review before you forget them • A built-in keypad; correct answers advance instantly, and mistakes show the right answer in place • A quick check-in after every 10 problems • Settings for haptics and which skill families to practice • Available in English, Simplified Chinese and Traditional Chinese — the app follows your device's Language setting Your progress stays on your device. Pure Math Drills has no ads, no accounts and no tracking. If you used version 1.1, your practice history carries over.

Youth Satellite Ground Station helps HAM amateur-radio operators, satellite observers and educators plan passes, check radio data and coordinate compatible antennas and radios. Observation and preparation • SGP4 orbit calculations; map, sky, ground and camera-overlay views • Azimuth, elevation, rise, culmination and set times; search, favorites and pass filters • Satellite AI Assistant: names and NORAD IDs, upcoming passes, IARU notices and sources, introductory guides • One-click Satellite preparation page brings together the satellite, equipment and pass task; optional calendar subscriptions and reminders Public radio records do not guarantee that a satellite is currently transmitting. Pro rotator control (additional purchase) Basic tracking tested: RC2500 over BLE; legacy DTrac Rotor over TCP with external sensor. Compatibility options*: RC-3040S, GS-232B controllers, Yaesu G-5500 with GS-232B, and compatible dual-axis EasyComm II controllers. Hamlib rotctld*: use the actual server backend, such as GS-232, EasyComm, SPID Rot2Prog, EA4TX ARS or AMSAT LVB Tracker. Pro radio control (additional purchase) Connection and frequency control tested on iOS: Icom IC-705 and ID-52A/E, using CI-V over compatible BLE. CI-V options*: ID-52 PLUS, IC-9700, IC-9100, IC-7100, IC-910H, IC-7300 and IC-7610. Yaesu CAT options*: FT-817/817ND, FT-818/818ND, FT-857/857D, FT-897/897D, FT-891, FT-991/991A and FTX-1. Previous FT-817ND frequency-reading tests used Android SPP, not iOS. DTrac Radio options*: Lianchang HG-UV88, Quansheng UV-K6 V3 and UV-K1; matching DTrac firmware and BLE hardware required. Benshi AP-2*: new experimental BLE control with compatible firmware; not physically validated. Hamlib rigctld*: an external server connects its supported radio backend, for example Icom, Yaesu or Kenwood TS-2000/TS-790. * These iOS device/connection combinations remain untested. Shared interfaces or protocols do not guarantee command compatibility. iOS does not support classic Bluetooth SPP or direct USB serial here. CAT/CI-V requires a matching BLE adapter or network bridge; Hamlib requires your own server. HF/50 MHz models such as IC-7300, IC-7610 and FT-891 do not cover typical VHF/UHF satellite bands. Frequency readback, Doppler, uplink/downlink and tone synchronization depend on the model. Rotator tracking, calibration and end-of-pass actions depend on the controller. Purchasing does not add hardware compatibility. External radios handle voice transmission; the app never automatically activates PTT. Follow local radio regulations. Audio-source and pass-recording planning controls are included. Actual audio capture, recording, export and built-in SSTV decoding are not enabled in this version. Chinese/English, light/dark themes and Beijing/UTC time; designed for iPhone and iPad. Purchases The free ad-supported tier includes satellite search, observation, pass prediction, public radio data and the AI Assistant. Ad-free Base is a one-time US$0.99 purchase. Base owners can purchase Pro for an additional US$9.90 to unlock compatible rotator/radio control: US$10.89 normal total in the US. These are separate non-consumables, not subscriptions. Promotions and regional prices are shown by Apple at purchase. Eligible V1.04 and earlier users retain their original device-control and ad-free rights. Existing Pro purchases remain valid. Restore with the original Apple Account; rights apply to that account's iOS/iPadOS version.