e: Spacetime Converter app icon

Apps Like e: Spacetime Converter for iPhone and iPad

Convert length and time relativistically.

The app converts between length and time using geometrized units where the speed of light is unity. It allows users to think about the world differently by converting units like inches to seconds or miles to years.

by Elliptics, Ltd.★ 5.01 ratingsEducationFreeData updated 2026-09-10

e: Spacetime Converter screenshots

Ranked alternatives

Showing 241–260 of 1,000 ranked alternatives.

  1. Mila's Fuel & EV Converter app icon

    Mila's Fuel & EV Converter

    Scott DeSapio

    Compare fuel economy across all units.

    The app converts between 16 different fuel economy units. It displays results in various formats for combustion and electric vehicles.

    ★ 4.86 ratingsUtilitiesFreeData updated 2026-10-11
  2. Gas Pipe Sizing Calculator app icon

    Gas Pipe Sizing Calculator

    Connor Kelley

    Calculate gas size based on BTU, length,

    Calculate gas size based on BTU load, length, and gas type (LP or Natural). Input values and select gas type to determine minimum size. Output result for immediate use.

    ★ 4.04 ratingsUtilities$1.99Data updated 2026-09-08
  1. Kelly Paper Basis to M-Weight app icon

    Kelly Paper Basis to M-Weight

    Manfred Breede

    Convert paper basis weight to M-weight.

    The app converts paper Basis Weight to M-Weight. Users input Basis Weight, Width, and Length, then select the paper type to see the M-Weight.

    ★ 0.00 ratingsBusinessFreeData updated 2026-09-29
  2. Franklin Electric AIM app icon

    Franklin Electric AIM

    Franklin Electric Co., Inc.

    Calculate cable length and gauge

    Access motor specifications by model number or rating. Calculate cable size for single or multiple submersible motor installations. Connect to technical resources and view helpful links to the AIM Manual website.

    ★ 4.85 ratingsUtilitiesFreeData updated 2026-09-12
  3. Kelly Paper M to Basis Weight app icon

    Kelly Paper M to Basis Weight

    Manfred Breede

    Convert paper M-Weight to Basis Weight.

    The app converts M-Weight to Basis Weight for paper. Users input M-Weight, Width, and Length, then select the paper type to see the Basis-Weight.

    ★ 0.00 ratingsBusinessFreeData updated 2026-09-29
  4. Air Flow Conversion Calculator app icon

    Air Flow Conversion Calculator

    Tan Chia Ling

    Calculate airflow rate instantly

    Calculate airflow displacement by inputting velocity or volume. Select duct type and dimensions with unit options. Instantly display results in preferred units including fl/min, m/s, and ft3/min.

    ★ 3.511 ratingsUtilities$2.99Data updated 2026-09-14
  5. Convert - Unit and Currency app icon

    Convert - Unit and Currency

    Raphael Odermatt

    Units and track rates

    Units across 17 categories with 398 options. Switch between currencies using real-time exchange rates for 130+ countries. Access the converter directly from Apple Watch.

    ★ 4.7126 ratingsProductivityFreeData updated 2026-09-09
  6. Fractio app icon

    Fractio

    James Campbell

    Calculate numbers in natural format.

    The app calculates linear measurements, areas, volumes, and weights in US and metric units. It supports decimal or fractional notation and includes unit conversion, memory, rounding, and percentage functions.

    ★ 3.211 ratingsUtilitiesFreeData updated 2026-10-21
  7. myConvert – Currency & Units app icon

    myConvert – Currency & Units

    Lu A Oo

    Convert units with one tap

    Convert units across 77 categories with over 1000 options. Perform multiple conversions on one screen. Add custom units and categories. Use built-in calculator and numeric keyboard. Convert complex measurements like height and weight between systems.

    ★ 4.968 ratingsTravel$2.99Data updated 2026-10-15
  8. Units: Smart Converter Pro app icon

    Units: Smart Converter Pro

    TrothMatrix OPC Private Limited

    Convert and currencies instantly

    Convert instantly with support for 12+ types including real-time currency rates. Switch between quickly. View accurate conversions and exchange rates. Save frequently used conversions for quick access.

    ★ 4.18 ratingsUtilitiesFreeData updated 2026-09-06

How we rank alternatives

Apps are ranked by functional similarity, category fit, rating confidence, and popularity.