Moonphase for Palm OS: Tracking Lunar Phases on a Palm Handheld

During the Palm OS era, dozens of small utilities gave handheld owners a pocket-sized window onto the night sky. One of the longest-lived was Moonphase (also listed as "Moon Phase" on its distributor's own pages) — a freeware application by developer Steven Kienle that drew a graphical picture of the Moon's current phase directly on a Palm device's screen. PalmGear, the largest Palm OS software catalog of the era, listed the program under product ID 1489, and it is that specific listing — not any of the other, unrelated "Moon Phase" titles that circulated for Palm OS over the years — that this restored page documents.

This article rebuilds Moonphase's history from archived PalmGear product pages (captured by the Wayback Machine at several points between 2000 and 2003), a corroborating modern listing on palmdb.net, and a contemporary astronomy-software roundup that cited PalmGear ID 1489 directly. Moonphase itself has not been available from any live storefront for over two decades; this page exists to preserve what can be verified about it, not to offer it for download.

Identifying the Right "Moonphase"

Palm OS had more than one lunar-phase utility over its roughly decade-long commercial life, and generic names like "Moon Phase," "MoonPhase," and "Lunar" were reused by different, unconnected authors. Before writing anything about features or history, it is worth being explicit about which program this page is about and how that identification was made.

The anchor for this article is a December 2002 "Computers in Astronomy" column by Don Shedrick, published in an astronomy-club newsletter titled "DAS Focus" and archived on a University of Delaware faculty page. The column surveys eleven Palm OS astronomy programs and links each one directly to its PalmGear catalog page. Its entry for Moonphase points to http://palmgear.com/software/showsoftware.cfm?sid=54905620021122082656&prodID=1489 — i.e., PalmGear product ID 1489, explicitly.

Using the Wayback Machine's archive of that exact PalmGear URL, this page's identity resolves unambiguously: PalmGear product ID 1489 was titled "Moon Phase" (versions 2.1 through 2.7 across the captures examined), developed by Steven Kienle, first submitted to PalmGear on June 17, 1998. A second, independent listing on the modern preservation site palmdb.net — uploaded in 2025 by a contributor unaffiliated with PalmGear — describes an identically named "Moon Phase" application, also credited to "Steven Kienle," with a matching version 2.7 and matching English/French file names. The agreement between a live-captured 2002–2003 PalmGear page and an independently sourced 2025 preservation listing is treated here as sufficient confirmation that these are the same program, and that it is the program the 2002 astronomy column was pointing readers to.

Note: Other Palm OS Moon-phase or lunar-observing utilities existed under similar names (for example, a program called "Lunar" turns up in later Palm software directories). None of the sources reviewed for this article connect those other titles to PalmGear product ID 1489, so they are out of scope here and should not be confused with the Kienle application described below.

What Moonphase Was

Stripped to its essentials, Moonphase was a small, single-purpose reference tool. PalmGear's own product description, unchanged across the archived captures from 2000 through 2003, reads: "This application will graphically display the phase of the Moon for any day. This version is corrected to work with any version of the PalmPilot, to my knowledge. The older pilots won't have the full functionality, however." German and French translations ("Mondphase" and a French-language "Moon Phase") were distributed as separate PalmGear listings by the same developer.

The 2002 "Computers in Astronomy" roundup, written independently of PalmGear's own copy, described the same program this way: it "will graphically display an image of the Moon showing its current phase, or the phase at any selected date," and it additionally "shows how many days into the lunar cycle you are, and when the next quarters, full, and new moons will be." That two independently written descriptions — one a retailer's product blurb, one a club newsletter's software review — agree on the core feature set gives reasonable confidence in what follows.

Developer and the PalmGear Listing

Moonphase was written by Steven Kienle, a Palm OS freeware author who also published a handful of other small utilities through PalmGear under the same developer account: a date-reminder tool called "Reminder," a Windows-side "PDB Reader" for viewing Palm Desktop backup files, a POSE (Palm OS Emulator) developer aid called "Save To Host," and the German and French translations of Moon Phase itself. No independent developer website for Kienle was located during research for this article; PalmGear's own developer page appears to have been the primary distribution point.

Graphical Display and Date Selection

Based on the corroborated descriptions above, Moonphase's core function was to draw a bitmap of the Moon reflecting its illuminated fraction for a given date, and to let the user step to a different date to see that date's phase instead — useful, per one 2003 PalmGear reviewer, for "fun to move thru the years... to see when the next full moon will occur on your birthday." The application also tracked and displayed the user's position within the current lunar cycle and surfaced the dates of the upcoming first-quarter, full, last-quarter, and new Moon, per both the PalmGear update log and the independent astronomy-column description.

An early bug-fix note (version 1.3, undated but preceding the earliest archived capture) is unusually specific and worth preserving verbatim, since it shows real design deliberation: the developer "added an option to allow for the Lunar Phase day count to start at 1, which is more social[ly] expected, rather than 0, which is more scientifically accurate," and adapted the device's scroll buttons so they could move between dates. Version 1.5 shortened the display of upcoming-phase dates to a "Month and Day" format "because of lack of screen space" — a small but telling detail about designing for a 160×160-pixel monochrome screen.

Two capabilities that period reviewers explicitly wished the program had — and which are therefore documented here as absent, not present — were moonrise/moonset times and a numeric illumination percentage. A 2001 review from a reader identifying as a night-vision-goggle pilot put it directly: "The only thing better would be moon rise/set times and illumination percentages (but that's found in other software.)" Two later reviewers (2002 and 2003) independently made the same request. No archived version of the PalmGear listing between 2000 and 2003 claims either feature, so this article does not attribute them to Moonphase.

Time-zone handling and the exact astronomical algorithm used for phase calculation are not documented in any source reviewed for this article and are not stated here.

Version History

The following table reproduces PalmGear's own "Update Description" changelog, as captured by the Wayback Machine, largely verbatim. Dates are given where PalmGear recorded them; several early version bumps were not individually dated in the surviving listing.

The mentions of "Moon!" and "Sol! II" in the version log are historically interesting but only partly verifiable: they were evidently separate freeware Palm astronomy programs popular enough that Kienle built optional interoperability with them into Moonphase's menu. No source reviewed here confirms who authored "Moon!" or "Sol! II," or whether they are related to any of the other programs covered in this restoration series, so no further claim is made about them.

Compatibility and Specifications

Price and Availability

Moonphase was freeware in every archived PalmGear capture examined, from the earliest (May 2000) through the latest live listing (June 2003) — PalmGear's "Product Type" field reads "Freeware" throughout, and no capture shows a price. Several reviewers explicitly praise it for being free ("Thanks for making it FREE!"). No shareware, registration-fee, or paid tier was found in any source.

The PalmGear product page for ID 1489 returned a redirect by August 2003 and a plain 404 by 2021, indicating the listing was eventually pulled down along with much of PalmGear's older catalog as the storefront changed ownership and structure over the years. No live, verified download source for Moonphase was identified during this research; this article does not provide one.

Contemporary User Reception

PalmGear's product page carried a running list of dated, attributed user reviews. A representative sample, quoted as archived:

Taken together, the review history is useful as evidence, not just color: it independently corroborates that the app lacked rise/set times and illumination percentages (three separate reviewers ask for them), confirms the color-vs-monochrome version split, and documents at least one specific device-compatibility complaint (the 2003 Sony Clié hard-reset report) that period users should have been aware of.

Moonphase vs. Larger Astronomy Suites

The same 2002 "Computers in Astronomy" column that pointed to Moonphase also surveyed larger, more ambitious Palm OS astronomy titles cataloged elsewhere on PalmGear — programs like Planetarium (sky maps of roughly 9,000 stars with celestial-position calculations), PleiadAtlas (an interactive deep-sky atlas), and RiseSet (dedicated rise, transit, set, and eclipse calculations). Compared to any of those, Moonphase was deliberately narrow: it did one thing — show the Moon's phase for a chosen date and flag the next few lunar milestones — and, per its RAM and download-size figures, did it in a fraction of the footprint.

That narrowness was arguably the point on Palm OS hardware of the late 1990s and early 2000s, where memory was measured in single-digit megabytes and every installed application competed for the same limited RAM. A 190 KB utility that answered one specific, frequently-asked question ("what phase is the Moon in, and when's the next full Moon?") had a place on a device even for users who also ran a full planetarium program, precisely because it didn't require loading star catalogs or running position calculations to answer that one question.

Plausible Period Uses

Grounded in what the archived reviews actually describe rather than speculation, documented real-world uses of Moonphase include: amateur astronomers planning observing sessions around dark-sky (new Moon) periods; a night-flying pilot using it alongside night-vision equipment to gauge ambient moonlight; and at least one user who used it as a practical reference for adjusting a mechanical grandfather clock's moon-phase dial. One reviewer's joking reference to using it for "advance warning" of full-moon-related mischief is best read as humor rather than a documented use case. This article does not attribute any lunar-mood or other pseudoscientific claims to the software or its users, since none appear in the sources reviewed.

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