ServiceCalc vs Zulu Time
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
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.
- Automated labor calculation
- Parts/materials totaling
- Configurable tax rates
- Built-in timer
- Flashlight function
- Customizable skins
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***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
Zulu Time
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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
Verdict
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
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.
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.
| Parameter | ServiceCalc | Zulu Time |
|---|---|---|
| Price | $0.99 | Free — better |
| Rating | 4.0 (4 ratings) — better | — |
| Positive reviews | 90.9% of reviews | — |
| Number of ratings | 4 — better | — |
| Update frequency | Every 2 months | Every 4 days — better |
| Ads | No | No |
| In-app purchases | No — better | Yes |
| Monetization | Paid | — |
| Devices | iPhone, iPod | iPhone, iPad, Apple Watch — better |
| Requires iOS | 12.0 — better | 17.0 |
| Further details — not scored | ||
| Size | 1 MB | 15 MB |
| Age rating | 4+ | 4+ |
| Developer | Farren Domenici | Yigit Can Akinci |
In-app purchases
ServiceCalc
No in-app purchases
Zulu Time
- Zulu Time Pro7 Days trial$1.991 Month
Questions
Is ServiceCalc free?
Is Zulu Time free?
Do ServiceCalc or Zulu Time have ads?
Which is updated more often, ServiceCalc or Zulu Time?
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