[General Topics] Skyica:
The search

To search Google Play, I have used

App Finder

, an advanced app search engine that has data for nearly 2.4 million apps.

I have also quickly searched the following alternative app stores directly:

Samsung Galaxy Store

Huawei AppGallery

Amazon App Store

F-Droid

Aurora store

APKMirror

AppBrain

SlideMe

Aptoide

However, I did not find additional apps that can be recommended.

App Finder

For our purpose, App Finder has several advantages over Google Play’s build-in search:

Search algorithm: Google Play uses a complex undocumented search algorithm that takes many factors into account, and prefers the apps it thinks “you’ll have a good experience with” (see

here

). While this is often very good for quickly finding some of the best apps, it is not suitable for a comprehensive search.

In contrast, App Finder matches your search query against the descriptions of the apps in a clear and easily comprehensible way (see below).

Search operators: In addition to the usual search operators, App Finder has some special operators. For example, to require specific words to occur in title or summary, which can be very helpful to exclude irrelevant apps.

Filters: While Google Play’s search has only filters for a user rating above 4 or 4.5 stars and for paid apps, App Finder has a filter for user rating in 0.1-star steps, and many other filters.

Sort options: Like Google Play, App Finder sorts the results by “relevance” by default. That is, by a score calculated from the match with the query, the average user rating, and the popularity. However, App Finder also has the option to sort by a single characteristic like the average user rating or the number of ratings, which gives us better orientation for comparing the results.

Result count: App Finder shows the exact result count, so we can add keywords or filters if there are more results than we want to inspect.

Result list: Unlike Google Play’s search, App Finder shows all essential data, summary, and screenshots directly in the result list.

Additional data: App Finder shows

the average user ratings with two decimals, which is relevant for high ratings (consider two apps rated 4.85 and 4.94 stars respectively, which are both rounded to 4.9 stars by Google Play),

the number of downloads with two significant digits, with is quite an improvement over Google Play which rounds them down to powers of ten times 1 or 5,

World-average user ratings in addition to country-specific ratings.

Here’s a how App Finder matches search queries against the app descriptions:

In the simplest case, if you just enter keywords separated by spaces, it returns exactly those apps where all the words (or forms of them, like the plural) appear in the description (or title or developer name).

.

Words inside quotes are required to appear in sequence (different forms of the words are still allowed).

.

+ in front of a word (or quoted words) requires it to occur in title or summary, not just anywhere in the description.

(The summary is a short description limited to 80 characters that the developer must provide).

.

- can be used as usual to exclude words. It can be combined with + to exclude them from title and summary only.

.

The usual OR operator is supported. Additionally, / (a slash) can be used instead of OR. Contrary to OR, / is evaluated first, which makes it often possible to avoid parenthesis and repetitions. Also, / can be used inside quotes. No spaces are required around /.

Simple Search

Since scientific calculator and graphing calculator are universally used terms, we would expect each app intended as such a calculator to have one of these terms in title or summary.

With App Finder, we can search for this using the query +”scientific calculator” OR +“graphing calculator” (see above). Using the / operator, it can be simplified to

Query 1: +“scientific/graphing calculator”

Without filters, this query gives 432 results.

Note that all searches in this article were done in Mai 2023 for the United States.

To not miss anything, I have looked through all results without filters.

Already from the screenshots, it is clear for most of the 432 apps that they are very low quality, or that they are not what we’re looking for.

Investigating the promising apps further, and quickly testing the still promising ones, I found that all the best apps probably have at least 4.5 stars average rating in the US for the full-featured version, at least 100 ratings, and were updated within the last year.

(Which is of course roughly what one would expect anyway.)

With these filters, we get 33 results. The following screenshots show the result list, ordered by number of ratings, which gives us a good orientation.

I have cut away some irrelevant apps, and placed the ad-supported and paid versions of the same apps together (future versions of App Finder will place apps by the same developer together automatically ).

Reading App Finder’s result list

The numbers left of the colorful stars are the average user ratings calculated by Google Play, the top one for the United States, the bottom one the whole world. (App Finder can also show the ratings for any other country supported by Google Play.)

The stars represent the rating distribution: The size (that is, area) of the stars is proportional to the number of 5-, 4-, 3-, 2-, and 1-star ratings (from green to red). Between different apps, the star-size is correlated with the total number of ratings at a logarithmic scale.

Paid apps without an indication do not contain ads. For apps with in-app purchases, the price range is shown in parentheses.

Spoiler content hidden.

Search by functionality

Since there may be advanced calculator apps that are not called scientific or graphing calculator by the developers, I have done a search by functionality mentioned in the description also.

It is of course very difficult to predict which features a developer would choose to include in the description and what words would be used.

But if we only refer to functionality that is very important and popular, and consider alternative descriptions, we can expect to miss only few good apps, if any.

Choosing differentiation, equation solving, and graphing as such functionality, we arrive at a query like

Query 2: differentiate/derivative equation/algebra graph/plot

(Remember that App Finder equates different forms of a word. E.g., calculate also searches for calculator, differentiate also for differentiation, and integrate also for integration and integral.)

(With the simpler query derivative equation graph we miss two relevant apps, Wolfram Alpha and Algeo.)

Without filters, this query gives 264 results.

Again looking through the list and testing promising apps I found that all the best apps here probably have at least 4.2 stars average rating in the US, at least 1 million downloads for the free version, and were updated within the last two years.

With these filters, the query gives 14 results. Below you see the complete list ordered by “relevance”.

While I had to try some different keyword combinations and filters to arrive at this, the result is quite impressive:

The list probably includes all the best advanced calculator apps, no irrelevant apps, only few apps which I would not recommend, and the app that I would rate as the best overall is first in the list.

Spoiler content hidden.

Additional searches

I have also repeated the query with -graph/plot instead of graph/plot to check if there are good advanced calculator apps without graphing, but this seems not to be the case.

I have searched for graphing apps specifically with graph/plot function trace and graph/plot function 3D. The latter query yielded 3 additional interesting 3D graphing apps (Grapher– Equation Plotter, Visual Math 4D, and Graphing Calculator 3D).

I have searched for CAS apps specifically with "computer algebra system", which yielded Maxima for Android and Xcas Pad.