Lekh Diagram

Lekh Digram is a sketch recognition diagram drawing app. It enables you to draw diagrams easily and quickly on tablet devices. It uses powerful shape recognition engine to recognize rough drawing and convert them into beautiful shapes and connection between them.

Lekh Diagram demo on iPad and iPhone:

Why Lekh Digram?

ipad (and other similar touch based devices) are great for reading/browsing. These devices also provide multi touch gestures for input which makes you feel much more natural way of interacting with devices than using keyboard and mouse. Despite of such great multitouch gestures, drawing diagram on these devices are painful (compared to drawing experience on PC). This is primarily because of

  • You finger is much thicker than mouse pointer. When you draw using finger or move any shape, you lose the precision that you get with mouse pointer. Your finger covers a large area beneath it and you can not accurately place.
  • The screen of such devices are relatively smaller which makes using a toolbox to select a shape and dropping it on drawing canvas painful.

The Lekh Diagram solves these problems and makes the diagram drawing much easier on iPad and iPhone. Lets see how


Shape recognition

The Lekh Diagram has powerful shape recognition engine. You draw rough shape using your finger and Lekh Diagram will recognize the shape. Apart from recognizing shapes, it also recognizes connections between shapes. Draw two or more shapes and connect them in various ways (using touch gestures), the Lekh Diagram will recognize those connections.

Example of Lekh Diagram shape recognition. In the images below, dark circle represents your finger while drawing
Your drawing Shape recognized by Lekh Diagram

Regularize shapes

For making a shape more regular, select the shape by tapping on that and then tap on the menu button shown on selection rectangle.
For example:
Original shape Regularized shape
Making sqaure
Rounded rectangle
Equilateral triangle

Connecting shapes

Your drawing Recognition

Drawing and erasing arrows

Using simple touch gesture you can draw arrows or erase at end points of a line, polyline and curves.
Your drawing Recognition

Customizing shapes by moving vertex and control points

The Lekh Diagram provides a powerful way of vertex/control point editing. You can modify/customize any shape by moving vertex or control points of the shape. The Lekh Diagram makes you to do this very preciously using "vertex handle". This is how it works:

Tap on any shape to select


vertices and control points are shown as dots on the selected shape. Tap on any vertex or control point to get the vertex handle


Now you can move the vertex by dragging the vertex handle placing your finger anywhere on the vertex handle. This way the vertex/control point that you are moving is not hidden behind your finger. So you can precisely place the point anywhere.

Similarly you can customize other shapes too. For example you can customize bezier curve by moving their control points



Scaling and rotating shapes

Lekh Diagram lets you to scale and rotate shapes using multi touch gestures.

Aligning shapes

The Lekh Diagram gives you a powerful way of moving and aligning shapes. It draws horizontal and vertical alignment line while you are moving any selected shape. It displays the center and and control points of other shapes while you are dragging a shape. This makes you to easily align shapes.


Adding Text

Adding text inside you diagram is very easy using Lekh Diagram. You can add text two ways:
  • Text as part of some shape like circle. For example if you add text on a circle, the text will be drawn with that circle always. If you move the circle, the text will automatically move.
  • Floating text. You can add text anywhere, move them and rotate them

Misc features

Apart from above, Lekh Diagram has many more features. Some of them listed here
  • inserting image from your photo album
  • undo/redo
  • deleting/cloning shapes
  • picking stroke/fill color
  • setting stroke width
  • making stroke dashed
  • flipping shape (horizontal and vertical)
  • selecting font/size/ color of text
  • exporting to email/ dropbox in various formats (jpeg, png, pdf svg and lekh format)
  • open Lekh Diagram files from email attachment
  • import Lekh diagram files from dropbox
  • change background (with various colors and patterns)
  • ability to include/exclude background in exported files
  • landscape and portrait mode

Screenshots