I was a Wikipedia editor before I discovered OSM, so I'm quite fond of this wiki for discussion and documentation, although I occasionally participate in Discourse forum and in the OSM Portugal Telegram chat.
I used to be an armchair mapper for most of my early years in the project, almost exclusively using the browser (first with Potlatch 1, then Potlatch 2, then with iD). Later I started doing some surveying with Mapillary. I did try Vespucci for mobile editing but never got comfortable with the interface. Then, when StreetComplete came out (and later Every Door), with more user-friendly interfaces, I finally started doing some more survey-based mapping. For a summary of my OSM contributions, see Pascal Neis' tools:
leaflet-providers preview — shows one main map at a time, with a list of a lot of other styles (or overlays) shown as thumbnails. Pretty good, but many of the thumbnails don't work.
TMS (Tile Map Service). [1] explains a bit the URL format
Simpler, based on static tiles that are fetched via zoom (z), latitude (y) and longitude (x) coordinates.
WMS (Web Map Service). [2] describes the URL format and parameters
More flexible, based on parameters like bbox, width and height
Apparently it's possible to use a tile proxy like MapProxy to convert between the two formats, but there doesn't seem to be a public hosted tile proxy instance that anyone can use.
Useful links
Raster tile providers — large table of tile providers. Includes the URL pattern; most (all?) of these use the TMS format.
Featured tile layers — the (currently 6) map styles featured on the OpenStreetMap web site. Indicates the max zoom of each tile layer.
F4Map supports toggling ground elevations, and attempts to place buildings smartly (probably the lowest point of the building matching the lowest point of the ground around it)
See Altitude for theoretical background, and the ele=* key for practical modeling.
ele=* refers to the elevation over the actual irregular mean sea level (geoid), which depends on the local crust density and other factors; ele:wgs84=* is used for elevation over the idealized reference ellipsoid
Both of these are absolute elevation measurements. There doesn't seem to be any support for relative elevation modeling, related to the ground around the feature (I don't know if there could be an unambiguous and stable way to specify that, anyway)
There are quite a few uses of elevation_from_road=*, but which road, and from what height of the road, if it's not level?
Shows three drag+zoom-synced maps: one for deleted elements, another for added ones, and a third map for modified ones.
Good for visualizing the geometry that's added/removed/modified, but not so much the diff in tags when nodes don't move
Map elements are interactive, and clicking on them pops up a tag diff table
Color highlight in tag diff table doesn't make it immediately clear what was added or removed (OSM History Viewer does this better IMO)
There's a bug? In the "State before the changeset" layer, relation 14614998 (which was introduced in the edit) is included rather than way 1011564190 (which was added to the relation). In fact, the relation shouldn't appear in the "modified" map at all (even with the "Current contribution" layer selected), since it didn't exist before.
Overall, the "State before the changeset" and "Current contribution" layers are unintuitively named
Color coding in the modified map is also not very intuitive (orange is used for elements where both geometry and tags changed, blue for elements where just the tags changed, and yellow elements where for just the geometry changed)
Node reshuffling (which nodes belong in each ways) is represented as a geometry change, even if the nodes don't move (so the ways don't move either)
Clicking on an element doesn't highlight it, so its unclear where its boundaries are if it touches other elements with the same types of changes
I have the bookmarklet installed in my browser, so I can open it from the OSM changeset page
Good for seeing the diff in tags (via color-coded tables), but the geometry visualization isn't very useful: added/deleted/modified elements can be toggled on/off, but they aren't color-coded, and not interactive (nor clicking an element in the list above highlights the element in the map)
It's the only one that shows all the tag additions/changes/removals at once, not requiring hovering or clicking the map elements. However, it does not show the map of each changed element (before/after) next to the corresponding tags table. There's only a single map at the end, and as mentioned above, it's not very interactive.
Also, it's pretty hard to navigate due to the tag diff tables automatically expanding when hovering the element names, and the map zoom via mouse scroll interfering with the regular page scroll (which is further complicated by the jumps due to the hover-triggeded content expansion). This was reported as early as 2011 (bug report copied to GitHub).
It would probably work better if they used <details> elements. The code to be changed is here and here
Not sure why * html .changed-object-tags-note is set to display:none in the line below; maybe it's to hide the hovering note when the page is embedded?
Maybe also make the map require ctrl+scroll to zoom, or not capture a scroll event that started outside the bounds of the map (i.e. was scrolling the page), or simply add padding around the map to allow scrolling around it? See info about possible solutions.
Open source but requires a Java running in a server. I wonder if this could be implemented fully client-side and hosted on GitHub pages or similar.
I have the bookmarklet installed in my browser, so I can open it from the OSM changeset page
The creator has discontinued this tool in favor of similar functionality incorporated in their more recent tool, FacilMap. It's not really the same, though. Compare:
Good interface (stable, responds well to mouse scroll, elements in the map are interactive, filters are always visible, table of changed tags uses intuitive colors, etc.)
Similar to OSMCha, but less overwhelming (focuses on a single changeset)
I have the bookmarklet installed in my browser, so I can open it from the OSM changeset page
elevation_from_road=*, but which road, and from what height of the road, if it's not level?
