The younger user generation that grew up with iOS and Android might consider my statement weird, but there are three indispensable basics for personal organizer apps:
- The most intuitive functional principle ("first law") to organize data is quite old (3000 years or so) and it is called 'files and folders'. — More precisely it is the ability to find categories (folders, method of loci) and names (files) that separate descriptively and logically its content. (No app and no OS' artificial intelligence can take that work out of your hands.)
- Each record in an organizer represents a file in the file system.
- The attributes that are associated with the files and organize them are stored (in the database file) next to the folder that contains the files. (Apple's HFS+ file system's .DS_Store files comply with this idea.  )
The Chikoo app can organize freely selected files from all of your folders, but if you store your files wisely, the app adheres to the three basics. So with Chikoo you have the best possible approach to organize your data on a Mac.
This article reviews Chikoo version 1.1.
What the Chikoo.app does
The Chikoo app provides lists of your files on a Mac to sort, search, filter, comment, and tag your data. It's not shortness that the appearance of Chikoo is very similar to a list of files in the Finder.
With a sidebar that provides sublists and filters its design is rational. It doesn't need to be different from the common mp3-library style (and indeed in its core Chikoo is a SQLite database).
The features make widely use of Core Services of the macOS (the file's standard attributes and the Smart Folders service). I appreciate that. It is clarity what users want. – And this way Chikoo can be (could be) an extended version of the Finder for the most important data folders on your Mac:
- all html files of your website (local mirror)
- all your markdown files providing lists of bookmarks
- all your notes files
- all your address files
- database management of your inventory
- your knowledge base: all the html files and snippets saved from the internet
When you import an entire folder Chikoo lists all files in it, including those of subfolders. You can not only view and sort by all file attributes (Date Modified, Size etc.), you can add as many comment (tag) columns as you need (click the image above).
What separates Chikoo from all the other notes and wiki apps ( see list at the bottom) is the ability to access the file system and to open a file with the appropriate editor (via Finder or Mou.app).
What the Chikoo.app not does
1. There is no button 'Open with..' (resp. 'Edit file..')
For example, when I double-click a html file in Chikoo, the file opens in the browser. But what if I want to edit the file?
To use first the 'Show in Finder' command and there the 'Open with..' command is stupid. The best solution woud be to have an Edit file.. button in the Chikoo Toolbar and a specification of the editor in its preferences.
2. There is no File content search
The application Nottingham 4 (that is also a SQLite database) demonstrates how it could work. The app imports automatically the complete content text of the files into a database field, so the search works not only for file names but also for the content.
Since another notes app Mou  lacks a file organizing and navigating feature, Chikoo (in an advanced version) would be quite a perfect completion for Mou. (For my needs the combination of Chikoo and Mou works already today better than Nottingham – since Mou is both, viewer and editor.)
3. There is no Strict syncing
I would like to have an option to choose, in which of two basic modes a new Chikoo library works when it is generated:
- a) cross-to-folders mode
Files in the Library are selectively imported and the locations of the files can be anywhere in the file system. (I can import entire folders, but the library stays in mode a).)
- b) one-folder sync mode
Recorded files in the Library are all the files of one specified folder - perhaps including those of subfolders (but can't be files of outside folders).
The Chikoo app in its current state is mainly a mode a) library. In some cases it tends to the mode b) – but not consequently.
There are commands like 'Import an entire folder' or 'Set up a library folder' – but that doesn't really mean mode b).
When I add afterwards files to the 'library folder' (in the Finder), Chikoo has no proper command to handle it. Instead of having a Sync button I have to add the according records manually, or I have to use the 'Import an entire folder' command again – that gives the same result. (But, applied multiple times to one folder, the command name sounds odd.)
Reversely, when I move afterwards a file in the Finder from the 'library folder' to a location outside, the Chikoo app accepts that and updates the path (what is correct only in mode-a).
For mode-b I would prefer the following behavior:
When I press a Sync button in the Toolbar (for all files at once) I get e.g. this popup window:
• Two files have been added in the Finder to the library folder.
• Three files have been either deleted in the Finder or changed its name/ folder/ subfolder.
The records in the Library will be added/ deleted now accordingly. — Resp. please relocate missing files. (Marked with (!) )
— OK —
Optional instead of a popup window these events should happen silently in the background with a short confirmation 'Synced'.
An application like Chikoo represents a lot of coding work and it would be unfair to call it in its current state only a draft. But it appears to me as if it lacks a few steps in development to make it obviously useful and attractive to everyone.
To bind different smart filterings to different folders is in my view this killer feature (besides the ability to search and to associate all sorts of comments to a file).
But for myself I have to admit, as long as Chikoo doesn't sync with its targeted folder with one click and as long as it doesn't search full text in multiple-files mode I give the advantages a miss and stay with the Finder.
Frankly speaking, what Chikoo can do can another app do (except for a broad columns view) easily: Little Bookmark Box 
On hypocritical aims of big players in the industry
Browsing locally through files (in hyperlink style) is cool. For nearly 15 years big IT companies tell us the web technologies and the desktop file system are merging.
But what happens is nothing. For security reasons it's prohibited that web browsers could trigger file events (Open with..).
As long as there is no local File Content Browser that can do both —follow local hyperlinks and open Finder folders / open other applications— personal organizer apps are all nonsense.
As far as I know the only apps that can do it today are Mou and Quiver (I guess against Apple's policy of 'jailed' applications).
In the end all these hyperlink-based personal organizers can organize themselves but not my stuff. A PC user needs the one single smart-filtered hub to reach his local files, the local folders, the bookmarked websites and services.
Addendum: Nevertheless, checking out the Chikoo software brings an old idea of mine to life again.
Wouldn't it be great if blog writers who write and publish without using online blogging services (and without content management frameworks on their computer) could simply use a SQLite-based tool to manage all the pages of their website?
With this idea in mind I separated already back then in my own site the html pages in one folder from the other stuff (like images) in another folder (+ subfolders etc.).
If I could code I could even upload the sqlite file and provide the content search feature online for my blog readers. — Greatest app ever for small web publishers.
Web links – Personal notes organizers
 In 2017 Apple will change its file system from (30 years old) HFS+ to the new Apple File System (APFS). It's not clear this step will pull the carpet from under Chikoo (the Core Services' File System Attributes of files or the Smart Folders service and savedSearches). Let's hope for the best.
 Mou.app works well with Chikoo since Mou is both, viewer (right) and editor (left) in concurrent display.
The render engine of Mou accepts a mix of markdown and markup (for some eye candy). I used it from 2011 to 2018.
Since the Mou app isn't maintained anymore I replaced it with Typora.
 OK., it's a misappropriation to use Little Bookmark Box for organizing local files instead of web bookmarks. But it works – at least with my dated version of macOS (10.11) and my dated version of LBB (2.2).
If you paste your local paths in the URL field file:///Users/... instead of http://... you can organize your local files. Even more: if you paste the text content of the file in the Note field, you can full-text search.
Filtering, tagging, categorizing, 'Open with..' – all works perfectly.
 It's useless when the local-only browser provides directory listing of the local file system – and can't trigger to open the various files in the respective default local application.
To get things straight concerning a browser that is able to (local-only) browse files I installed the Coda app on an iPhone. – And –lo and behold– it works. You can run both at the same time, a secure browser for own local files and one for the Internet.
— But for common purposes Coda's internal browser is much too hidden. (And Apple wants it this way.)
 Addition 2018: With its features to navigate and browse (hyperlink-style) Boostnote did almost manage to outclass my farorite - the combination of Chikoo and Mou - also because Chikoo and Mou have not seen any further development in the last two years.
 TiddlyWiki could be as well the missing link to navigate through all my note files and inventory – if it wouldn't depend on Firefox but provide instead a secured local-only Browser with the ability to open files in their respective default apps (e.g. in TiddlyWiki clicking a link to a local md file should open the file in the md editor resp. web links should open up in the "Internet-Firefox").
Suitable for humans is this: a so-called mind palace, the method of loci.
 Addition 2019-02: For a few weeks I switched to Quiver app. – Quiver is like Mou, but it provides an integrated file management (JSON), a searchable hierarchy of Library/ Notebooks/ Notes/ Cells. Well, it is not what I meant when I demand 'Files and Folders': Quiver hides its file structure as 'Package Contents'.
But the method of loci works well inside the apps UI (and in an emergency JSON is human-readable).
Then I switched again. There is something even better: Typora offers syncing/ mirroring between Finder hierarchy (files and folders) and the app's own file tree panel. Perfect.
Allegedly for a higher level of scientific work the method Zettelkasten (Niklas Luhmann) is preferred. But I am not a friend of bypassing the need of well-naming categories and a knowledge system by my own. ('Roam'-like promises are dupery.)