How to estimate development (& testing) effort of a project ?

[Steven]

Hello World,

I've been working on defining requirements and functionality of a multi-platform app and am now at the point where I'd like to estimate the cost of developing it.

I have defined screens with known fields & levels of complexity (eg. easy, average, difficult), underlying activities (& their complexity), and messages between platforms.

What I need now is a general 'rule-of-thumb' for estimating the development & unit-testing effort in man-hours. (I can multiply the resulting number by the developers' hourly rate to get cost )

Do the numbers differ between platforms ? (ie. is Android 'harder' than IOS, or BB, Windows Mobile, etc. ? )

[maxkatz]

Interesting question. Just to clarify, estimates using Tiggr or mobile app development in general?

[Steven]

Well, based on my experience, development effort is directly related to the tool(s) used, so, ... Tiggr-specific.

But, if you're also aware of effort estimates with other tools, I'm all ears ...

Thanks,
Steve.

[maxkatz]

Are you able to share the requirements with us?

[Steven]

Well, in terms of my original question, I don't understand what additional requirements you're looking for (please re-read).

I simply want to know how you estimate project effort: what rules-of-thumb do you use ?

[maxkatz]

Here is what we use.

Assumptions:
-Back-end/web services are REST and well documented
-Functionality is well documented
-UI is defined

Easy screens: 4-6 days/platform
Average: 7 -10 days/platform
Difficult: 12-15/platform

[Steven]

OK, thanks !

Would you be able to break those those numbers down (eg. by %-age) between UI, functionality, & web services ?

For example, would it be 25% / 50% / 25% respectively, or 20% / 60% / 20%, ... ?

[maxkatz]

I don't really know.. it depends on the app. If you would like, we can take this offline (email: max at exadel dot com). It might be easier and we can exchange more information.