Comparison

Periodic vs 555 Timer & Oscillators Pro

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

Head to head
About

Periodic

Features
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The PeriodicTableElements is an elegant app that is interactive and fun. Easy to use, easy to understand, simple and effective. It shows the periodic table of elements in variety of ways 1) Classic grid with name that is color coded. You can configure it to look however you like. 2) Visually appealing electron distribution. 3) Visually appealing Lewis dot structure. 4) List that can be sorted based on different element properties like group, period, category etc. These awesome periodic tables can be shared by simple double click anywhere on the table. It is possible to copy the periodic table diagrams as high quality SVG xml. Drag your finger on the periodic table canvas to update elements automatically or tap on an element to see more details. Tap on an element and all the rest of the related elements are highlighted. Details of a selected element is shown in a beautifully drawn animated element. Tap on the animated element and you will see more details that can also be shared. Tapping on the list element will navigate you to a page that shows details of the element. It automatically saves your hard work locally on your device so you can come back and pick up from where you left off as your great effort will not be lost. This is a perfect app if you are a student learning chemistry. This is an app for all student groups. From high school to college to university students. Be creative. Enjoy the app!

About

555 Timer & Oscillators Pro

Features
Currently charting
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Master the design of oscillators and waveform generators using 555 timer integrated circuits, digital logic integrated circuits, operational amplifiers, and transistors. The application provides a comprehensive collection of over 130 tutorials and circuit diagrams, covering 555 timer circuits and practical applications, CMOS 4000 series logic oscillators, TTL 74LS and 74HC series oscillators, operational amplifier–based waveform generators, and transistor multivibrators. Designed for electronics beginners, students, hobbyists, and professional engineers, the app serves as a complete reference and learning tool for designing, understanding, and building oscillators, multivibrators, pulse generators, and waveform circuits commonly used in both analog and digital electronics. In addition to tutorials and schematics, the app includes built-in calculators for frequency, timing, duty cycle, and component value estimation, helping users quickly calculate and adjust circuit parameters. All topics are presented with clear circuit diagrams and detailed explanations. Available in 14 Languages: β€’ English, French, German, Indonesian, Italian, Japanese, Polish, Portuguese, Russian, Simplified Chinese, Spanish, Turkish, Ukrainian, and Vietnamese β€” study in your native language! Covered Topics: β€’ 555 Timer IC Series β€’ Astable, monostable, and bistable modes β€’ Pulse Width Modulation (PWM) β€’ Voltage conversion circuits β€’ Sensor and external module interfacing β€’ CMOS Logic Oscillators β€’ CMOS 4000 series circuits β€’ Astable, monostable, and bistable modes β€’ Gated CMOS oscillators β€’ TTL / HC Logic Oscillators β€’ TTL 74LS series circuits β€’ 74HC series logic oscillators β€’ Astable and monostable modes β€’ Operational Amplifier Oscillators β€’ Sine wave generators β€’ Square-wave pulse generators β€’ Triangle wave generators β€’ Transistor-Based Oscillators β€’ Transistor-Based Astable multivibrators β€’ Transistor-Based Monostable multivibrators The Pro edition provides additional tools for faster learning and easy navigation: β€’ Full-text search across all lessons and components β€’ Favorites for saving and organizing important topics The content is regularly updated and expanded with each new release, ensuring the latest tutorials and circuit examples are always available.

Screenshots

Periodic4 screens
555 Timer & Oscillators Pro4 screens

Verdict

The call

The clearest difference is update cadence: Periodic at every 5 weeks against 555 Timer & Oscillators Pro's every 3 months. Periodic also leads on price ($1.99 vs $4.99). 555 Timer & Oscillators Pro's advantage is chart position (#193 vs unranked). On ads, in-app purchases, device support and iOS requirement there is nothing between them.

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

CostPrice Β· In-app purchases Β· Ads Β· Monetization

Periodic costs $1.99 and 555 Timer & Oscillators Pro $4.99 up front. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

Periodic ships an update every 5 weeks, 555 Timer & Oscillators Pro every 3 months. The most recent releases landed on October 11, 2026 and October 12, 2026 respectively.

Scorecard3 real differences Β· 4 level
Periodic versus 555 Timer & Oscillators Pro: the parameters behind the verdict, then further details
ParameterPeriodic555 Timer & Oscillators Pro
Price$1.99 β€” better$4.99
Update frequencyEvery 5 weeks β€” betterEvery 3 months
AdsNoNo
In-app purchasesNoNo
Best chart rankβ€”#193 β€” better
DevicesiPhone, iPad, iPodiPhone, iPad, Mac
Requires iOS15.1 β€” better16.0
Further details β€” not scored
Size31 MB22 MB
Age rating4+4+
DeveloperOm Prakash ChapagainALG Software Lab

In-app purchases

None

Periodic

No in-app purchases

None

555 Timer & Oscillators Pro

No in-app purchases

Questions

Is Periodic free?
Periodic costs $1.99, with no in-app purchases.
Is 555 Timer & Oscillators Pro free?
555 Timer & Oscillators Pro costs $4.99, with no in-app purchases.
Do Periodic or 555 Timer & Oscillators Pro have ads?
Neither Periodic nor 555 Timer & Oscillators Pro shows ads.
Which is updated more often, Periodic or 555 Timer & Oscillators Pro?
Periodic ships an update every 5 weeks, and 555 Timer & Oscillators Pro every 3 months. Most recently, Periodic was updated on October 11, 2026 and 555 Timer & Oscillators Pro on October 12, 2026.

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