Comparison

ServiceCalc vs Zulu Time

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

Head to head
About

ServiceCalc

This tool automates invoice calculations for service technicians, reducing errors and time spent. It handles labor, parts, tax, and totals, with features like a built-in timer and flashlight.

Highlights
  • Automated labor calculation
  • Parts/materials totaling
  • Configurable tax rates
  • Built-in timer
  • Flashlight function
  • Customizable skins
Features
Read full description

***FEATURED IN KEYNOTES MAGAZINE*** ServiceCalc cuts time spent and reduces errors when totaling invoices out in the field. This tool automates and displays the Labor, Parts/Materials, Tax, and Total. ServiceCalc is ideal for Locksmiths, Electricians, Plumbers, or any other service technicians that frequently write up invoices. Conventional Method: -Sub total line items on invoice -Add up labor on a standard calculator -Write down labor on invoice -Clear the calculator's screen -Add up parts/materials -Write down on invoice -Multiply tax rate -Write down on invoice -Clear calculator's screen -Add labor, parts, and tax -Write total on invoice ServiceCalc Method: -Sub total line items on invoice -Add up labor and tap Labor button -Add up parts and tap Parts button*** -Write down totals on invoice ***Parts are added per line. The timer is used to create a delay when making a single multiplication. This delay gives you enough time to read its subtotal to then transfer onto the invoice.*** After tapping Parts you can turn your iDevice sideways (landscape) for a larger readout. Quickly add the desired labor by tapping the half hour or full hour buttons. Two tax rates are configurable to allow multiple jurisdictions. The secondary tax rate can also be used as a tip calculator. Built in flashlight function for illuminating your invoice. 3 Skins to choose from: Original, Blue Steel, and Magnum ---------------------------------- Totals truncate to 2 decimal places. Tax is rounded up to the hundredths when the halfway point is a value of 5 or higher. Example: if tax = 2.775, actual tax = 2.78 if tax = 2.77445, actual tax = 2.78 if tax = 2.771, actual tax = 2.77 ---------------------------------- Compatibility: iPhone / iPod touch on iOS 8.0 or later and iPad on iOS 12.0 or later. Found a bug? Something not working? Have a suggestion? Feel free to contact me via email: farren@phoxlocks.com

About

Zulu Time

Features
Read full description

Zulu Time brings Zulu (UTC), local time, world-clock planning, UTC alarms, and original instrument-inspired displays together in one focused app. AT A GLANCE • View live Zulu and selected local time side by side. • Configure Zulu and local time independently: 24-hour, 12-hour, or military format, optional seconds, and separate date styles. • Detect your current time zone automatically and refresh it as needed, or manually choose from 111 countries/regions and 126 cities and aviation hubs. PLAN THE SAME MOMENT WORLDWIDE • Select an exact UTC date and time up to seven days ahead or behind. • Move by 15 minutes, one hour, or one day. • Compare the same moment across saved world clocks with UTC offsets, DST status, and day-boundary indicators. • Read ISO 8601, aviation DDHHMMZ, and YYDDD ordinal codes. ZULU ALARMS • Schedule alerts directly in UTC and review the local-time conversion before saving. • Create one-time, daily, or weekly alarms. • Choose sound on or off and snooze for 10 minutes. ORIGINAL THEMES • Choose from 17 brand-neutral designs: six modern aviation displays, seven premium analog dials, and four minimal themes. • Supported aviation themes can use the on-device compass for live heading; heading scales in other themes are decorative. • Premium dials display both Zulu and local time without covering the dial. IPHONE, IPAD & APPLE WATCH • Configurable Home Screen, Lock Screen, and StandBy widgets. • A full Apple Watch app with all 17 themes. • Zulu/local and Zulu/date complications. • Sync the selected place, time zone, theme family, and verified subscription status from iPhone. PRIVATE BY DESIGN • No ads. • No Zulu Time account. • No cross-app tracking. Zulu Time requires an auto-renewing monthly subscription. Eligible new subscribers can receive a 7-day free trial. The localized price and renewal terms are shown before confirmation, and the subscription can be managed or canceled in Apple Account settings. The aviation displays are visual clock themes only. They are not calibrated or certified flight instruments and must not be used for navigation. Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

Screenshots

ServiceCalc4 screens
Zulu Time4 screens

Verdict

The call

The clearest difference is price: Zulu Time at Free against ServiceCalc's $0.99. Zulu Time also leads on update cadence (every 4 days vs every 2 months). ServiceCalc's advantage is in-app purchases (none vs 1) and iOS requirement (12.0 vs 17.0). On ads and device support 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

Zulu Time is free to download; ServiceCalc costs $0.99 up front. Zulu Time sells 1 in-app purchase, starting at $1.99 per month. ServiceCalc asks for nothing beyond the download.

UpkeepUpdate frequency

ServiceCalc ships an update every 2 months, Zulu Time every 4 days. The most recent releases landed on October 10, 2026 and October 24, 2026 respectively.

Scorecard4 real differences · 6 level
ServiceCalc versus Zulu Time: the parameters behind the verdict, then further details
ParameterServiceCalcZulu Time
Price$0.99Free — better
Rating4.0 (4 ratings) — better—
Positive reviews90.9% of reviews—
Number of ratings4 — better—
Update frequencyEvery 2 monthsEvery 4 days — better
AdsNoNo
In-app purchasesNo — betterYes
MonetizationPaid—
DevicesiPhone, iPodiPhone, iPad, Apple Watch — better
Requires iOS12.0 — better17.0
Further details — not scored
Size1 MB15 MB
Age rating4+4+
DeveloperFarren DomeniciYigit Can Akinci

In-app purchases

None

ServiceCalc

No in-app purchases

1 purchases

Zulu Time

Subscriptions1
  • Zulu Time Pro7 Days trial$1.991 Month

Questions

Is ServiceCalc free?
ServiceCalc costs $0.99, with no in-app purchases.
Is Zulu Time free?
Zulu Time is free to download, with in-app purchases available.
Do ServiceCalc or Zulu Time have ads?
Neither ServiceCalc nor Zulu Time shows ads.
Which is updated more often, ServiceCalc or Zulu Time?
ServiceCalc ships an update every 2 months, and Zulu Time every 4 days. Most recently, ServiceCalc was updated on October 10, 2026 and Zulu Time on October 24, 2026.

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