Features
/ Operating System 
Desktop
OS  Linux 64 bits (Asus 1215B, AMD C50 @ 1.0 GHz) 
Android
(Asus Transformer, NVidia Tegra 2 Cortex A9 @ 1.0 GHz) 
iOS (iPad, Apple A4 Cortex A8 @ 1.0 GHz. iPad 2, Apple A5 Cortex A9 @ 1.0 GHz)  Maemo
4 (Nokia N810, TI OMAP 2420 ARM11 @ 400 MHz) 
Maemo
5
(Nokia N900, TI OMAP 3430 Cortex A8 @ 600 MHz) 
MeeGo
Harmattan (Nokia N9, TI OMAP 3630 Cortex A8 @ 1.0 GHz) 
Symbian
(Nokia E71, Freescale MXC300 ARM 11 @ 369 MHz) 
Installation
type 
Simple,
using repositories 
Complex,
with many steps to install SL4A, Python and then SymPy manually 
Simple, by installing 'Python Math' (free) or 'Python for iOS' (US$2.99) from App Store  Simple, using repositories  Simple, using repositories  Not
so simple, with manual download of SymPy package 
Complex, with many steps to install PyS60 2.0 and then SymPy manually 
SymPy
version 
0.7.1 
0.7.1 
0.6.7
('Python Math') 0.7.1 ('Python for iOS') 
0.7.1 
0.7.1 
0.7.1 
0.7.1 
Time
to load 
0.58
s 
2.22
s 
8.89
s ('Python Math' @ iPad), 6.33 s ('Python for iOS' @ iPad 2) 
7.52
s 
2.76
s 
1.66
s 
52.6
s 
Time to run "integrate (x**5/(alpha*x**2+beta)**2,x)"  1.83
s 
2.79
s 
3.75 s ('Python Math' @ iPad), 3.16 s ('Python for iOS' @ iPad 2)  34.2
s 
10.8
s 
5.60
s 
22.8
s 
Easy of interactive use : Command history, full completion, object information, etc.  Yes   
Command
history. Object information (only in 'Python for iOS'). 
Yes 
Yes  Yes  Only
limited command history 
isympy (using IPython) availability  Yes 
 
 
Yes, with IPython 0.10.2  Yes, with IPython 0.10.2  Yes, with IPython 0.10.2 
 
Easy
of editing SymPy/Python (sourcecode editors with color highlighting,
command completion, object information, etc) 
Yes 
Few
editors with some features 
Few
editors with some features 
Few editors with some features  Few editors with some features  Few editors with some features  'PED'
(works only with PyS60 1.4.5) 
'Plot()'
for 2D and
3D graphics 
Yes 
 
 
 
Yes 
 
 
AndroidPython is available as part of SL4A (Scripting Layer for Android). So look at Scripting Layer for Android (SL4A) web site and installing interpreters section to install SL4A and Python. I suggest SL4A_r5x (for smartphones) or SL4A Tablet Remix (for tablets) because they have some UI bugs fixed.To install pure Python modules on Android, it is very symple, just put the directory/files in "/sdcard/com.googlecode.pythonforandroid/extras/python/". So, to install SymPy, download 'sympy_0.7.1android.zip' and unzip it, copying its 'sympy' directory and 'isympy.py' file to "/sdcard/com.googlecode.pythonforandroid/extras/python/". To use SymPy interactively, open 'SL4A', then select 'View > Interpreters > Python 2.6.2'. To load SymPy, type "from isympy import *". "from sympy.abc import *" is useful because it defines a lot of extras variables. 
iOSFrom App Store :

Maemo 4 Diablo and Maemo 5 FremantleFollow the SymPy (Computer Algebra System) for Maemo 4 & 5 & 6 topic in Talk Maemo.org, i.e., enable extras repository, search for SymPy in the application manager and install "SymPy Interactive Shell", it will install SymPy and IPython (if not installed before). Tap the SymPy icon to launch IPython interactive shell loading SymPy with some initialization (of variables and output type). 
MeeGo 1.2 HarmattanFollow the SymPy (Computer Algebra System) for Maemo 4 & 5 & 6 topic in Talk Maemo.org, i.e. :

SymbianSymPy needs PyS60 v2.0.0 (which runs Python 2.5.4), but PyS60 1.4.5 (which has Python 2.2.2) is also useful because there are many PyS60 softwares incompatible with PyS60 v2.0.0. For example, PED, the best Python source code editor for Symbian, needs PyS60 1.4.5. To install PyS60 1.4.5, download from the PyS60 project the files 'PythonForS60_1_4_5_3rdEd.sis' and 'PythonScriptShell_1_4_5_3rdEd.sis' (assuming that you have a Symbian S60v3 or newer smartphone) and install them. It is recommended to install PyS60 1.4.5 in drive "E:", before installing PyS60 v2.0.0.Install PyS60 v2.0.0 following the 'Getting Started' section of the 1st chapter of 'Python on Symbian' book. Install PyS60 in drive "E:". SymPy needs to be installed manually in "E:\Python\Lib\", so, on "E:" drive, create a "Python" directory with subdirectory "Lib", if they don't exist. Download 'sympy_0.7.1symbian.zip' and unzip it, copying its 'sympy' directory, 'isympy.py' and 'timeit.pyc' files to "E:\Python\Lib\". To use SymPy interactively, open 'Python 2.0.0', then 'Options > Interactive console'. To load SymPy, type "from isympy import *". "from sympy.abc import *" is useful because it defines a lot of extras variables. To edit SymPy/Python scripts, use PED. But to run scripts using SymPy, use Python 2.0.0. 
Plot Window Keyboard Controls
=============================
Screen Rotation:
X,Y axis Arrow Keys, A,S,D,W, Numpad 4,6,8,2
Z axis Q,E, Numpad 7,9
Model Rotation:
Z axis Z,C, Numpad 1,3
Zoom: R,F, PgUp,PgDn, Numpad +,
Reset Camera: X, Numpad 5
Camera Presets:
XY F1, G
XZ F2, H
YZ F3, J
Perspective F4, K
Sensitivity Modifier: SHIFT
Axes Toggle:
Visible F5, T
Colors F6, Y
Close Window: ESCAPE
Screenshot: F8, I
=============================
Also, the sensitivity of keyboard and mouse/stylus control was
increased on Maemo 5 OS, with or without the 'SHIFT' modifier for smooth
3D movements.SymPy Plot of a function of 1
variable, y = f(x), a dumped harmonic
oscillator :
"Plot(2.5*exp(1.0*x/2)*cos(pi*x), [0,10,150], width=800, caption='Dumped harmonic oscillator')". Timing : 12s / 2s (repeated). 
SymPy Plot of a 2D parametric
function of 1 variable, x = f(t), y =
g(t), an explosion : "Plot(t*sin(8*t)*cos(8*t)*cos(t),
t*sin(8*t)*cos(8*t)*sin(t),
[0,4*pi,1600], width=800, caption='Parametric Explosion',
axes='stride=1.0')". Timing : 57s / 17s (repeated).

SymPy
Plot of a polar function, r = f(theta=t), a rose with 8 petals :
"Plot(cos(4*t), [200], 'mode=polar', width=800, caption='Polar Rose',
axes='tick_length=0.02; stride=0.1')". Timing : 15s / 4s (repeated).

SymPy
Plot of a 3D parametric curve of 1 variable, x = f(t), y = g(t), z =
h(t), a wire 3D curve : "Plot((2+cos(16*t))*cos(t),
(2+cos(16*t))*sin(t), sin(16*t), [800],
axes='colored=true', width=800, caption='Wire 3D curve')". Timing : 51s
/ 9s (repeated).

SymPy
Plot of a 3D surface in cartesian coordinates, z = f(x,y), a surface z
colored : "Plot(5*x*y*exp(x**2y**2), [2,2,100], [2,2,100],
'color=zfade4',
axes='colored=true', width=800, caption='Surface z colored')". Timing :
36s / 30s (repeated).

SymPy
Plot of a 3D surface in cylindrical coordinates, r = f(theta=t,z=h), a
wormhole : "Plot(z**2/4+1,
[], [z,3,3], 'mode=cylindrical; style=both; color=zfade4',
axes='colored=true', width=800, caption='Wormhole surface')". Timing :
25s / 16s (repeated).

SymPy
Plot of a 3D surface in spherical coordinates, r = f(theta=t,phi=p), an
oscillating spherical surface : "Plot(1
+ sin(5*t)*sin(10*phi)/10, [t,0,2*pi,80], [phi,0,pi,80],
'mode=spherical; color=zfade4', axes='colored=true', width=800,
caption='Oscillating spherical surface')". Timing :
34s / 22s (repeated).

SymPy
Plot of a 3D parametric surface of 2 variables, x = f(u,v), y = g(u,v),
z = h(u,v), a moebius strip : "Plot((2+(v/2)*cos(u/2))*cos(u),
(2+(v/2)*cos(u/2))*sin(u), (v/2)*sin(u/2), [u,0,2*pi,80], [v,1,1,20],
'color=zfade4', axes='colored=true', width=800, caption='Moebius
strip')". Timing : 19s / 7s (repeated).
